Piston Sealing Cooling via Sliding Skirt Thrust Ring Flow Valve
Solution Overview
Problem
The piston sealing device with high pressure causes inadequate lubricating and cooling due to pronounced tightness, leading to insufficient fluid flow and energy dissipation, especially in hydraulic pumps and motors, where existing solutions like oil injectors complicate the system and fail to reach inaccessible areas.
Innovation Solution
A cooling and lubricating system that includes a sliding skirt thrust ring, flow valve, intermediate fluid exit chamber, valve return spring, and flow calibration orifice to generate a leakage flow of oil, ensuring minimal energy and volume reduction, avoiding the need for additional injectors, and providing lubrication to inaccessible zones with minimal cost increase.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the piston sealing device is designed with pronounced tightness to reduce fluid leakage, then sealing performance is improved, but lubricating and cooling efficiency deteriorates due to insufficient fluid flow
Solution Approach 1:
The piston sealing device is divided into multiple functional segments: a continuous extensible segment for sealing and discrete thrust rings with flow valves for lubrication. This segmentation allows the sealing function to be optimized independently from the lubrication function, enabling pronounced tightness while maintaining sufficient fluid flow for cooling through the flow calibration orifices in the thrust rings.
Solution Approach 2:
Intermediary flow calibration orifices are introduced in the thrust rings to mediate between the high-pressure fluid chamber and the lubrication zones. These orifices provide a controlled fluid passage that maintains sealing effectiveness while ensuring adequate lubricating and cooling fluid flow to the piston and mechanical parts.
2Loss of energy
If additional oil injectors are added to improve lubrication and cooling, then lubricating and cooling efficiency is improved, but device complexity increases
Solution Approach 1:
The thrust rings serve multiple functions: they provide mechanical support as end stops, maintain sealing contact through spring pressure, and deliver lubrication through integrated flow calibration orifices. This multi-functionality eliminates the need for separate oil injectors, improving lubricating and cooling efficiency without increasing device complexity.
Solution Approach 2:
The system uses the existing high-pressure fluid from the fluid chamber to provide its own lubrication and cooling through the flow calibration orifices in the thrust rings. This self-service approach eliminates the need for external oil injection systems, maintaining energy efficiency while avoiding additional system complexity.
3Reliability
If the continuous extensible segment is pressed in circumferential contact against the cylinder to achieve near-total tightness, then sealing performance is improved, but lubrication and cooling of mechanical parts deteriorates
Solution Approach 1:
The sealing system is segmented into the continuous extensible segment for tightness and separate thrust rings with flow valves for lubrication. This allows the extensible segment to be pressed in circumferential contact against the cylinder for near-total tightness while the thrust rings independently provide lubrication and cooling fluid flow to mechanical parts.
Solution Approach 2:
The thrust rings act as intermediary elements that provide controlled fluid flow through flow calibration orifices, mediating between the high-pressure fluid chamber and the lubrication zones. This ensures that even when the extensible segment achieves near-total tightness, adequate lubrication and cooling fluid can still reach mechanical parts through the thrust ring orifices.
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 system achieves substantial lubrication and cooling with minimal energy loss and cost, maintaining near-perfect tightness and reducing friction losses, while ensuring adequate lubrication and cooling of the piston and mechanical parts without complicating the hydraulic system.
Implementation Method 1
a flow valve (22) traversed axially and more or less in tight manner by the interskirt mechanical connection (13) and inserted between the continuous extensible segment (15) and the piston head (6)... a flow calibration orifice (27) passing straight through said valve (22) in the axial direction
Implementation Method 2
a sliding skirt spring (20) which tends to bring the sliding skirt (12) closer to the fixed skirt (7) and to axially compress the continuous extensible segment (15) or at least prevent said sliding skirt from moving away from the fixed skirt in the manner of an end stop
Implementation Method 3
the larger this force, the more energy is dissipated by friction and shear of oil at the interface between the piston and the cylinder. In order to carry away this energy, there must be sufficient oil circulating
Data Source
AI summary
The cooling and lubricating system is provided for a piston sealing device for a piston, which includes a fixed skirt and a sliding skirt joined together by an interskirt mechanical connection to axially compress a continuous extensible segment under the action of a sliding skirt spring. The system adds to the device a sliding skirt thrust ring so as to insert between the fixed skirt and the continuous extensible segment a flow valve traversed by the interskirt mechanical connection. The valve is held at rest away from the fixed skirt by a valve return spring on the one hand, and including a flow calibration orifice on the other hand.