EV Transmission Parking Lock Venting Against Pressure and Lubricant Ingress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of a parking lock in a transmission housing of an electrically driveable vehicle poses challenges due to the presence of lubricants and higher temperatures, leading to potential functional failures of the parking lock actuator caused by pressure differences.
Innovation Solution
A pressure equalization apparatus is implemented, connecting the interior of the parking lock actuator to the exterior of the transmission housing in a gas-permeable manner through a lead-through element and fluid guiding element, preventing lubricant penetration and ensuring robust operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the parking lock is integrated in the transmission housing, then construction space is saved, but the parking lock actuator becomes sensitive to lubricant penetration and pressure differences
Solution Approach 1:
The patent divides the transmission housing into two separate spaces: a lubricant-containing space for the transmission elements and a lubricant-free space for the parking lock actuator. This segmentation prevents lubricant penetration into the actuator while maintaining the compact integrated design, thus preserving construction space savings while improving actuator reliability.
Solution Approach 2:
The patent introduces a pressure equalization apparatus as an intermediary component between the lubricant-containing space and the lubricant-free space. This apparatus includes a pressure equalization line with a check valve that equalizes pressure differences without allowing lubricant passage, thereby protecting the actuator from both pressure-induced failures and lubricant contamination.
2Reliability
If the parking lock actuator is sealed to prevent lubricant ingress, then reliability improves, but pressure differences cause functional failures
Solution Approach 1:
The pressure equalization apparatus acts as an intermediary that selectively balances pressure between the two spaces. The check valve mechanism allows pressure equalization in one direction while blocking lubricant flow, thus eliminating harmful pressure differences without compromising the actuator's protection from lubricant ingress.
Solution Approach 2:
The patent employs a diaphragm or membrane in the pressure equalization apparatus that can flexibly respond to pressure differences. This flexible element allows pressure equalization while maintaining a barrier against lubricant penetration, effectively decoupling the pressure and contamination protection functions.
3Reliability
If a complex sealing system is used to prevent lubricant penetration, then reliability improves, but device complexity increases
Solution Approach 1:
The pressure equalization apparatus with its check valve mechanism provides a relatively simple intermediary solution that simultaneously addresses both pressure differential and lubricant contamination issues. This approach is simpler than implementing complex multi-layer sealing systems while achieving the same reliability goals.
Solution Approach 2:
The pressure equalization apparatus serves multiple functions: it equalizes pressure differences, prevents lubricant penetration, and maintains the integrity of the actuator's lubricant-free environment. This multi-functionality reduces the need for separate complex sealing systems, thereby lowering overall device 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 solution effectively prevents lubricant ingress, enhancing the robustness and reliability of the transmission device by equalizing pressure and reducing the risk of functional failures, while being easy to implement and maintain.
Implementation Method 1
a pressure equalization apparatus (14), by means of which an interior of the parking lock actuator (8) is connected to an exterior of the transmission housing (9) in a gas-permeable manner
Implementation Method 2
connected to an exterior of the transmission housing (9) in a gas-permeable manner
Implementation Method 3
a fluid guiding element (17), the first end of which is connected to the interior of the parking lock actuator (8) and the second end of which is connected to the lead-through element (16)
Data Source
AI summary
Described is a transmission device (1) for an electrically driveable vehicle having a transmission element (2), a parking lock (6), by which the transmission element (2) can be blocked and which has a parking lock actuator (8), and a transmission housing (9), which encloses the transmission element (2) and the parking lock (6). A pressure equalization apparatus (14) is connected to an exterior of the transmission housing (9) in a gas-permeable manner. The pressure equalization apparatus (14) has a lead-through element (16) which passes through a transmission housing opening (15) and a fluid guiding element (17), the first end of which is connected to the interior of the parking lock actuator (8) and the second end of which is connected to the lead-through element (16).