Hydraulic Control System for Automatic Transmission ETRS
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hydraulic control systems for automatic motor vehicle transmissions with electronic transmission range selection (ETRS) lack performance during default conditions, where electronic control is lost, often resulting in undesirable shifts to neutral or park, and fail to provide multiple drive states.
Innovation Solution
A hydraulic control system for automatic transmissions that includes a two-position default disable solenoid valve, ETRS valve, Park servo, position sensors, default disable valve, drive select valve, various orifices, blow-off valves, main and auxiliary pumps, torque converter, torque converter regulator, and control valve, along with linear force solenoid valves and clutch regulation valves to manage clutch and brake actuators, enabling multiple drive states during default conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If electronic transmission range selection (ETRS) system is used to reduce mechanical components and enhance styling options, then ease of manufacture and adaptability are improved, but reliability during default conditions deteriorates as the transmission may shift to neutral or park unintentionally
Solution Approach 1:
The hydraulic control system is pre-configured with default valve positions and hydraulic pathways that automatically engage Park or neutral gear when electronic control is lost. The default disable solenoid valve and ETRS valve are designed with spring biases and default positions that ensure safe default states without requiring active electronic signaling during failure conditions.
Solution Approach 2:
The system incorporates redundant hydraulic pathways and default disable solenoid valves that act as backup mechanisms. When electronic control fails, these pre-positioned hydraulic components automatically take over to prevent uncontrolled gear shifts, cushioning against the harmful effects of loss of electronic control.
2Reliability
If hydraulic control system is designed to shift to neutral or park during default conditions, then safety is improved, but adaptability deteriorates as multiple drive states cannot be provided
Solution Approach 1:
The ETRS valve is designed with the ability to be dynamically positioned in multiple states (Park, neutral, or specific drive ranges) based on the state of the default disable solenoid valve. When the solenoid is energized, the system can access multiple drive states; when de-energized, it defaults to safe states. This dynamic configuration allows the system to adapt between safety and versatility based on operational conditions.
Solution Approach 2:
The hydraulic control system is designed with multi-functional valves and pathways that can serve multiple purposes. The ETRS valve and default disable solenoid valve combination can provide both safe default operation (Park/neutral) and multiple drive states when needed, making the system universally capable of both safety and adaptability functions through shared components.
3Reliability
If mechanical connection with shifting cable is used for transmission range selection, then reliability during default conditions is improved, but device complexity increases due to additional mechanical components
Solution Approach 1:
The patent replaces traditional mechanical shifting cables and linkages with an electronic transmission range selection system that uses solenoid valves and hydraulic pathways to control gear selection. The hydraulic control system with default disable solenoid valves provides the necessary reliability during default conditions without requiring complex mechanical connections, substituting mechanical complexity with electronic-hydraulic control.
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 ensures the transmission can maintain forward gear and Park options during default conditions, preventing random operation and providing reliable gear shifting, thus enhancing safety and performance.
Implementation Method 1
hydraulic control system includes a two position (on-off) default disable solenoid valve, an ETRS valve, an ETRS or Park servo, position sensors, a default disable valve, a drive select valve, various orifices and blow-off valves as well as main and auxiliary pumps
Implementation Method 2
the clutches and brakes are controlled by hydraulic actuators or operators controlled by the outputs of a plurality of spool valves in a valve body
Implementation Method 3
controlled by solenoids under the control of a transmission control module (TCM)
Implementation Method 4
a plurality of interconnected planetary gear assemblies which cooperate with friction clutches and brakes to provide a sequence of forward gears and reverse
Data Source
AI summary
A hydraulic control system for a multiple speed motor vehicle automatic transmission having electronic transmission range selection (ETRS) provides both a forward gear ratio and Park options during default conditions where the transmission loses electronic control when the ETRS system is in a drive mode. The hydraulic control system includes a two position default disable solenoid valve, an ETRS valve, a park servo, position sensors, a default disable valve, a drive select valve, various orifices and blow-off valves as well as main and auxiliary pumps, a torque converter, a torque converter regulator and control valve and a plurality of linear force solenoid valves and clutch regulation valves which control a like plurality of clutch and brake actuators.