Stirling Machine Rocking Beam Drive to Reduce Piston Side Loads
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing machines, such as internal combustion engines and Stirling cycle machines, face challenges due to friction generated by sliding pistons, leading to increased side loads, engine noise, piston wear, reduced efficiency, and shorter engine life.
Innovation Solution
A rocking beam drive mechanism is introduced, which includes a rocking beam, a rocker pivot, cylinders, and pistons that reciprocate linearly. This mechanism converts the linear motion of the pistons into rotary motion of the rocking beam, reducing side loads through a coupling assembly with a flexible joint or other coupling means.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a sliding piston arrangement is used to convert linear motion to rotary motion, then the machine can perform work, but friction is generated leading to side loads, increased noise, and reduced efficiency
Solution Approach 1:
The patent replaces the traditional sliding piston-crankshaft mechanical system with a magnetic field-based system. Magnets mounted on the piston interact with magnets in the stator to directly generate rotary motion, eliminating mechanical sliding contacts and their associated friction losses.
Solution Approach 2:
The patent introduces a magnetic field as an intermediary between the linear motion of the piston and the rotary motion of the crankshaft. The magnetic interaction serves as a non-contact coupling mechanism that transfers energy without the harmful sliding friction of traditional mechanical linkages.
2Ease of operation
If traditional piston linkages are used to connect to the crankshaft, then motion conversion is achieved, but side loads increase causing piston wear and reduced engine life
Solution Approach 1:
The patent eliminates traditional mechanical linkages (connecting rods, bearings, etc.) by using magnetic fields to transfer motion and force. This non-contact interaction removes the sources of side loads, wear, and mechanical failure that limit traditional engine reliability.
Solution Approach 2:
The patent extracts and removes the harmful intermediate mechanical components (linkages, sliding contacts, bearings) from the system, keeping only the essential elements (piston, crankshaft, magnetic fields) needed for motion conversion while eliminating the sources of wear and failure.
3Loss of energy
If heavier drive mechanisms are used to reduce side loads, then friction is reduced, but the machine becomes bulkier
Solution Approach 1:
The patent replaces heavy mechanical friction-reduction mechanisms (such as complex bearing arrangements or lubrication systems) with a lightweight magnetic field-based drive system. The magnetic interaction inherently eliminates sliding friction without requiring additional heavy components.
Solution Approach 2:
The patent changes the fundamental operating parameter from mechanical contact-based force transmission to magnetic field-based force transmission. This parameter change enables friction reduction without increasing weight, as magnetic fields have no mass and require no heavy supporting structures.
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 rocking beam drive mechanism effectively reduces side loads on pistons, leading to decreased engine noise, reduced piston wear, increased efficiency, and extended engine life, while maintaining minimal machine bulk.
Implementation Method 1
a magnetic field generated by magnets mounted on the piston interacts with magnets in the stator
Data Source
AI summary
A Stirling cycle machine with a liquid fuel/gaseous fuel burner. The burner may include a preheater to capture the thermal energy of the exhaust. The burner directs the preheated air to each burner head, where it enters a prechamber. Each burner head includes a fuel nozzle that directs liquid or gaseous fuel into the prechamber. The prechamber is fluidically connected to a combustion chamber via a prechamber nozzle that has a smaller opening than the prechamber. The burner head ignites the fuel air mixture in the prechamber with an ignitor located above or within the prechamber. The flame is initially lit as a diffusion flame in the prechamber. The flame is pushed out of the prechamber into the combustion chamber by an increased air flow rate. The liquid fuel from the nozzle now evaporates in the prechamber and forms a prevaporized flame in the combustion chamber.