Supercharger Coupling with Elastomeric Dampening
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Roots-type superchargers generate unwanted noise due to solid borne noise caused by fluctuating loads on timing gears and rotor shaft bearings, particularly during low-speed operation, and misalignment between the input shaft and rotor shaft.
Innovation Solution
A coupling assembly with a central hub and elastomeric inserts between the input and rotor shaft couplings, providing dampening through a series of steps and arcuately shaped insert bodies to absorb rotational energy and account for misalignment, thereby reducing noise and gear bounce.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If meshed timing gears are used to drive rotors in a Roots-type supercharger, then the rotors can be timed in relationship to each other, but gear rattle and bounce occur causing solid borne noise during low-speed operation
Solution Approach 1:
A coupling assembly with elastomeric inserts is introduced as an intermediary between the input shaft and rotor shaft. The elastomeric material absorbs vibrations and fluctuations from the timing gears, preventing them from being transmitted to the rotor shaft and causing noise, while still maintaining the necessary timing relationship.
Solution Approach 2:
The coupling assembly changes the mechanical parameters between the input and rotor shaft by using elastomeric inserts that provide dampening. This alters the transmission characteristics to reduce gear rattle and bounce while maintaining functional timing.
2Stability of the object's composition
If a rigid coupling is used between input shaft and rotor shaft, then precise timing is maintained, but misalignment and runout between shafts cause increased noise and vibration
Solution Approach 1:
The coupling assembly uses elastomeric inserts that provide flexibility to accommodate misalignment and runout between the input shaft and rotor shaft. This flexible connection reduces noise and vibration while maintaining adequate timing precision for supercharger operation.
3Power
If timing gears are subjected to fluctuating loads from engine firing pulses, then power is transmitted to the rotors, but solid borne noise is generated during low-speed operation
Solution Approach 1:
The coupling assembly with elastomeric inserts serves as a mediator that allows power transmission from the input shaft to the rotor shaft while absorbing the fluctuating loads and vibrations caused by engine firing pulses, thereby reducing solid borne noise during low-speed operation.
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
The coupling assembly effectively minimizes noise and gear bounce by providing torsional and axial damping, ensuring smooth operation and reducing the impact of misalignment between the input and rotor shafts.
Implementation Method 1
The first and second elastomeric inserts can provide dampening between (i) the first coupling and the central hub and (ii) the second coupling and the central hub
Implementation Method 2
A first plurality of elastomeric inserts can be received by the first plurality of openings. The first plurality of elastomeric inserts can receive first portions of the plurality of coupler pins
Data Source
AI summary
A coupling assembly arranged between an input shaft and a rotor shaft of a supercharger can include a first coupling, a second coupling, a central hub and a plurality of coupler pins. The first coupling can be mounted for concurrent rotation with the input shaft. The second coupling can be mounted for concurrent rotation with the rotor shaft. The central hub can be disposed intermediate the first and second couplings. The central hub defines central hub bores therein. A plurality of coupler pins can be received in the central hub bores. A first plurality of elastomeric inserts can receive first portions of the plurality of coupler pins. A second plurality of elastomeric inserts can receive second portions of the plurality of coupler pins. The first and second elastomeric inserts can provide dampening between (i) the first coupling and the central hub and (ii) the second coupling and the central hub.