Two-Speed Differential Gear With Integrated Coupling Device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hybrid drive systems for electric vehicles require significant installation space and energy for decoupling mechanisms, especially when implementing two-speed transmissions to achieve both starting performance and high vehicle speeds, leading to increased design effort and energy consumption.
Innovation Solution
A transmission and differential gear design with a coupling device that allows the ring gear of the input stage to be non-rotatably coupled or decoupled to the housing or planetary carrier, using a form-fitting coupling mechanism that can be integrated in a space-neutral manner, enabling two gear stages without additional radial or axial space and allowing load-free switching between gears.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If two separate friction clutches are used to couple the ring gear to the housing and carrier, then two different gear ratios can be selected, but a lot of installation space is required and energy consumption increases due to continuous actuation force
Solution Approach 1:
The patent combines the functions of two separate friction clutches into a single friction clutch mechanism. The single clutch couples the ring gear of the input stage to either the housing or the carrier, enabling two different gear ratios without requiring two separate clutch assemblies. This merging reduces installation space while maintaining the ability to select between two gear ratios.
Solution Approach 2:
The single friction clutch is designed to perform multiple functions: it can couple the ring gear to the housing for one gear ratio, couple the ring gear to the carrier for another gear ratio, and potentially decouple the input stage entirely. This multi-functional design eliminates the need for separate clutch assemblies for each coupling scenario.
2Adaptability or versatility
If two separate friction clutches are used to achieve two different gear ratios, then adaptability is improved, but energy consumption increases due to continuous actuation force
Solution Approach 1:
By merging two separate friction clutch actuation systems into a single friction clutch mechanism, the patent reduces the total actuation force required at any given time. Only one clutch needs to be actuated to achieve the desired gear ratio change, thereby reducing continuous energy consumption compared to maintaining two separately actuated clutches.
3Area of stationary object
If separate planetary gears connected coaxially in series are used, then the required overall gear ratio is achieved with little radial and axial installation space, but the design complexity increases
Solution Approach 1:
The patent merges two separate planetary gear stages into a single integrated planetary gear stage where the ring gear of the input stage can be coupled to either the housing or the carrier. This integration maintains the compact coaxial design while simplifying the overall structure by eliminating the need for completely separate planetary gear assemblies connected in series.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The gear (1) has a housing (25) provided with two input shafts (2) that are arranged with output shafts (3, 4). A sun gear (12) of an input stage (6) is operatively connected to the input shafts. A load stage (7) comprises a housing-fixed ring gear (13). A planet gear (17) of the load stage is operatively connected to input shafts of a compensation section (5). A ring gear (19) of the input stage is arranged in a coupling device (KV) and non-rotatably coupled or decoupled to a planet carrier (18) of a planet wheel (16) and the input stage. The coupling device comprises a coupling ring (26). The planet carrier is designed as separate components and integrated components.