Variable Displacement Oil Pump Axial Size Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing variable displacement oil pumps require large axial sizing due to the need for a drain passage and partitioning wall, which complicates the design and increases size.
Innovation Solution
A variable displacement oil pump design that eliminates the need for an axial oil passage between control oil chambers by using a drain chamber partitioned with respect to the first and second control oil chambers, allowing direct hydraulic pressure-based biasing for volume variation, thus avoiding the intervention of an oil passage in the axial direction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a drain passage and partitioning wall are installed to supply drained oil to the main gallery, then the feedback control function is achieved, but the axial size of the pump increases
Solution Approach 1:
The drain chamber is merged with the control oil chambers such that the drain chamber is partitioned with respect to the first and second control oil chambers. This integration eliminates the need for separate drain passages and partitioning walls, achieving feedback control while reducing axial size.
Solution Approach 2:
The drain chamber serves multiple functions: it collects drained oil from the drain section, provides feedback pressure to control the volume variation, and is integrated with the control oil chambers. This multi-functionality eliminates the need for separate drain passages while maintaining the feedback control function.
2Reliability
If a partitioning wall is added to separate control oil chambers, then the hydraulic pressure control is improved, but the device complexity increases
Solution Approach 1:
The drain chamber is partitioned with respect to the first and second control oil chambers, creating hydraulic separation without requiring additional partitioning walls. This integrated design maintains hydraulic pressure control while reducing structural complexity.
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 design reduces the axial size of the pump, enabling a more compact and efficient oil pump that can supply oil to the internal combustion engine without the need for additional axial passages, thereby minimizing size and operational delays.
Implementation Method 1
a biasing member installed in a state in which a pre-load is acted and which biases the movable member in a direction in which the volume variation quantity of the plurality of pump chambers is increased
Implementation Method 2
a first control oil chamber which serves to generate a biasing force in a direction in which the volume variation quantity of the plurality of pump chambers is decreased for the movable member according to a hydraulic pressure introduced from the internal combustion engine; a second control oil chamber which serves to generate the biasing force in a direction in which the volume variation quantity of the plurality of pump chambers is increased for the movable member according to the hydraulic pressure introduced from the internal combustion engine
Implementation Method 3
a drain chamber partitioned with respect to the first control oil chamber and the second control oil chamber and which serves to generate the biasing force in a direction in which the volume variation quantity of the plurality of pump chambers is varied on a basis of the hydraulic pressure directly introduced from the drain section
Data Source
AI summary
In a variable displacement oil pump, a drain chamber 36 partitioned with respect to first and second control oil chambers 31, 32 and which serves to generate a biasing force in a concentric direction based on a pump drain pressure directly introduced from a drain port 22a is interposed between first control oil chamber 31 which serves to generate a biasing force in the concentric direction in which a volume variation quantity of a plurality of pump chambers PR for a cam ring 15 based on a control pressure as a main gallery pressure introduced from an internal combustion engine and second control oil chamber 32 which serves to generate the biasing force in an eccentric direction in which the volume variation quantity of the plurality of pump chambers PR is increased for cam ring 15 based on the control pressure.