Positive Displacement Pump Unloading Plate for Parasitic Loss Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fluid management systems in vehicles experience parasitic losses due to excess fluid flow, which is not converted into functional energy, leading to energy inefficiencies, especially when the engine is idling, and current solutions to reduce these losses are costly and complex.
Innovation Solution
A positive displacement pump with an unloading device, such as a resiliently biased plate, that moves away from the pumping gears upon pilot pressure application, creating an open chamber to reduce pressure development and minimize parasitic losses without additional costly devices or complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a positive displacement pump is used to transfer hydraulic fluid, then fluid transfer function is achieved, but parasitic losses increase due to excess fluid flow not converted to functional energy
Solution Approach 1:
The pump system dynamically adjusts its operation between two states: a closed chamber state for normal fluid transfer under pressure, and an open chamber state for reducing parasitic losses during idle or low-demand conditions. The movable member transitions between positions to change the chamber volume, enabling the system to adapt its fluid transfer characteristics to match actual operational requirements and minimize energy waste.
2Loss of energy
If additional devices such as clutches or external unloading valves are used to reduce parasitic losses, then energy efficiency improves, but device complexity and cost increase
Solution Approach 1:
The unloading function is merged directly into the pump structure itself through a movable member that is part of the pump housing. This integrated approach eliminates the need for separate external unloading valves or clutches, reducing system complexity while maintaining the ability to reduce parasitic losses. The movable member's position directly controls chamber volume, combining the functions of fluid containment and pressure regulation in a single component.
3Loss of energy
If a movable member is used to change chamber volume, then parasitic losses are reduced by creating open chamber, but device complexity increases
Solution Approach 1:
The movable member is biased by a spring element that automatically positions it to change chamber volume in response to system pressure conditions. The spring bias provides a self-regulating mechanism that reduces parasitic losses without requiring external control systems, actuators, or complex control logic. The system serves itself by using the inherent mechanical properties of the spring to maintain optimal chamber volume.
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 solution effectively reduces parasitic losses by allowing the pump to operate without developing pressure when not needed, thereby saving power and fuel, and maintaining efficiency and cost-effectiveness.
Implementation Method 1
A bias element is disposed between the wall and the movable member
Implementation Method 2
A fluid applied to the passage into the second cavity changes the bias force of the bias element and the location of the movable member with respect to the interior wall to change a volume of the first cavity
Data Source
AI summary
A fluid transfer pump that has a housing, a body portion movable within the housing between a first position and a second position, a gear coupled to the housing, a body cavity defined partially between the body portion and the housing, and an aperture defined in the housing that selectively provides a fluid to the body cavity. When the fluid is applied to the body cavity at or above a pilot pressure, the body portion is in the first position adjacent to the gear and when the fluid is applied to the body cavity at a fluid pressure lower than the pilot pressure, the body portion is in the second position and spaced from the gear.