Vehicle Transmission Jet Pump Separable Nozzle Cavitation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional automatic transmissions experience cavitation in the transmission pump due to insufficient fluid acceleration at high engine speeds, leading to reduced flow rate, wear on components, and noise pollution, with existing jet pump designs being inflexible and reliant on precise component tolerances.
Innovation Solution
A separable nozzle configuration within the hydraulic control system that directs a jet stream through a center section, allowing for adjustable nozzle designs and independent specification of jet velocity, independent of adjacent component dimensions, thereby reducing cavitation and enhancing pump inlet pressure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a nozzle is integrated into a cast housing, then the structural integrity is improved, but the flexibility to alter jet pump geometry is reduced and manufacturing costs increase
Solution Approach 1:
The nozzle is separated from the cast housing and provided as a distinct, replaceable component. This segmentation allows the nozzle geometry to be modified independently without altering the housing structure, thereby maintaining structural integrity while enabling design flexibility and reducing manufacturing costs for geometry changes.
Solution Approach 2:
The nozzle is designed as a dynamic, adjustable component rather than a fixed integral part of the housing. This allows the jet pump geometry to be altered by replacing or adjusting the nozzle component, providing adaptability while the housing maintains its structural role.
2Ease of manufacture
If two components are positioned to create a nozzle-shaped passage, then manufacturing flexibility is improved, but the velocity of the jet stream becomes dependent on precise component fit and stack up tolerances
Solution Approach 1:
The nozzle function is extracted from the housing and embodied in a dedicated nozzle component. This component is designed with precision features that define the jet stream velocity independently of the housing tolerances, thereby reducing dependence on stack up tolerances between multiple components.
Solution Approach 2:
The separate nozzle component acts as an intermediary element that mediates between the housing and the fluid flow. It provides a precisely controlled passage geometry that determines jet stream velocity, isolating the velocity control function from the tolerance accumulation of multiple component interfaces.
3Reliability
If the jet stream is directed through the center section of the nozzle, then reliance on adjacent component dimensions is reduced, but the complexity of positioning and aligning the nozzle increases
Solution Approach 1:
The nozzle is designed with localized features that ensure proper positioning and alignment, such as locating surfaces, guide pins, or keyed features. These local quality enhancements at critical interfaces provide reliable centering of the jet stream while the overall design maintains simplicity through the use of a single integrated nozzle component rather than multiple precision-mated parts.
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 cavitation in the transmission pump by increasing pump inlet pressure, allowing for flexible nozzle designs and improved robustness against component variability, while maintaining efficient fluid flow and reducing noise pollution.
Implementation Method 1
produce a jet stream of fluid, pulled from a fluid reservoir, through a center section of the nozzle
Implementation Method 2
reduces the tendency for cavitation within the pump
Implementation Method 3
produce a primary stream of fluid that converges with the jet stream of fluid
Data Source
AI summary
The present disclosure relates to a vehicle transmission with jet pump. The jet pump includes a hydraulic control system that has a nozzle fitted between a first and second housing. The nozzle is separable from the first and second housing. The hydraulic control system is configured to produce a jet stream of fluid through a center section of the nozzle.