Hydraulic Valve Unit Design for Transmission Gear Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hydraulic systems for motor vehicle transmissions are costly and complex due to the high number of valves required to control multiple gear-selection pressure chambers, which increases installation space, weight, and cost.
Innovation Solution
A simplified hydraulic system design that connects two selection valve units directly to ten gear-selection pressure chambers, using a configuration with different switching pressure thresholds and control pressures to efficiently manage actuation and control pressures, reducing the number of valves needed while maintaining the ability to switch a high number of transmission gears.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a high number of valves are used to control multiple gear-selection pressure chambers, then the transmission can switch a high number of gears, but the system complexity, installation space, weight, and cost increase
Solution Approach 1:
The selection valve unit is designed to perform multiple functions by selectively connecting different gear-selection pressure chambers through a single valve mechanism. The valve can direct actuation pressure to various pressure chambers depending on the selected transmission gear, allowing one valve unit to control multiple gears instead of requiring separate valves for each pressure chamber
Solution Approach 2:
Multiple valve functions are merged into a single selection valve unit. The patent integrates the functionality of multiple valves into one unified valve assembly that can route actuation pressure to different gear-selection pressure chambers through its internal switching mechanism, thereby reducing the total number of valve components in the system
2Adaptability or versatility
If a high number of valves are used to control multiple gear-selection pressure chambers, then the transmission can switch a high number of gears, but the installation space and weight increase
Solution Approach 1:
Multiple valve functions are merged into a single selection valve unit. The patent integrates the functionality of multiple valves into one unified valve assembly that can route actuation pressure to different gear-selection pressure chambers through its internal switching mechanism, thereby reducing the total number of valve components in the system
3Adaptability or versatility
If a high number of valves are used to control multiple gear-selection pressure chambers, then the transmission can switch a high number of gears, but the system cost increases
Solution Approach 1:
The selection valve unit is designed to perform multiple functions by selectively connecting different gear-selection pressure chambers through a single valve mechanism. The valve can direct actuation pressure to various pressure chambers depending on the selected transmission gear, allowing one valve unit to control multiple gears instead of requiring separate valves for each pressure chamber
Solution Approach 2:
Multiple valve functions are merged into a single selection valve unit. The patent integrates the functionality of multiple valves into one unified valve assembly that can route actuation pressure to different gear-selection pressure chambers through its internal switching mechanism, thereby reducing the total number of valve components in the system
4Ease of operation
If different switching pressure thresholds are used for different selection valve units, then selective control of valve units is improved, but the control system complexity increases
Solution Approach 1:
Different selection valve units are assigned different local characteristics in the form of distinct switching pressure thresholds. Each valve unit has a uniquely configured spring element that provides a specific pressure threshold, allowing the control system to selectively activate particular valve units based on the required transmission gear by applying appropriate control pressures
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 configuration results in a compact, lightweight, and cost-effective hydraulic system capable of switching more than seven forward transmission gears, saving on installation space, weight, and costs while improving controllability.
Implementation Method 1
the second selection valve unit is directly connected to four gear-selection pressure chambers in order to transmit actuation pressure and the third selection valve unit is directly connected to 6 other gear-selection pressure chambers and directly to the second selection valve unit in order to transmit actuation pressure
Implementation Method 2
at least the first selection valve unit and the second selection valve unit have different switching pressure thresholds, as well as with at least one first control valve, which is connected in control terms at least to the first selection valve unit and the second selection valve unit and which is provided in order to set at least two control pressures which are different from one another
Data Source
AI summary
The transmission includes at least ten gear-selection pressure chambers which are provided for the selection of a plurality of transmission gears, at least two actuation valves, each of which is provided for setting at least one actuation pressure for the gear-selection pressure chambers, at least one first selection valve unit, at least one second selection valve unit, and at least one third selection valve unit which are provided for connecting the actuation valves to the gear-selection pressure chambers. The second selection valve unit is directly connected to four gear-selection pressure chambers in order to transmit actuation pressure and the third selection valve unit is directly connected to six other gear-selection pressure chambers and directly to the second selection valve unit in order to transmit actuation pressure.