Shifting Sleeve Drivetrain Coupling for Parking Lock Sequencing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing drive train systems face challenges in efficiently transmitting torque and locking the drive wheels, often requiring separate actuating elements and risking damage due to misalignment and incorrect state detection.

Innovation Solution

A drive train design utilizing a shifting sleeve with axially displaceable torque interfaces that sequentially couples the drive motor to the drive wheel for torque transmission and to the parking lock unit for locking, facilitated by a spring-loaded actuating mechanism and displacement sensors for precise state detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If separate actuating elements are used for the parking lock and friction clutch, then each component can be actuated independently, but the device complexity increases and the risk of misalignment and damage increases

Engineering Contradiction:

Improverisk of misalignment and damageVSAvoidnumber of actuating elements

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines the actuation of the parking lock and friction clutch into a single actuating element with a unified actuation direction. The shifting sleeve integrates both functions by sequentially establishing different torque interface couplings along a single axial displacement path, eliminating the need for separate actuating elements and reducing misalignment risks.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The single actuating element is designed to perform multiple functions by sequentially coupling different torque interfaces. The shifting sleeve can couple the drive motor to the drive wheel for torque transmission, then subsequently couple the drive wheel to the parking lock unit for locking, all through one actuating mechanism with a common actuation direction.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Device complexity

If a single shifting sleeve is used to sequentially couple torque interfaces, then the device complexity is reduced, but the manufacturing precision requirements increase to ensure proper alignment

Engineering Contradiction:

Improvenumber of shifting sleevesVSAvoidalignment of torque interfaces

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The shifting sleeve is designed with different local coupling characteristics at different axial positions. Each torque interface (drive motor interface, drive wheel interface, parking lock interface) has specific coupling features optimized for its function, allowing the single shifting sleeve to achieve precise local alignments without requiring overall system complexity.

Inventive Principle:

Principle #3Local quality

3Adaptability or versatility

If the axial extension of the torque interface is increased to enable sequential coupling, then the coupling flexibility is improved, but the length of the shifting sleeve increases

Engineering Contradiction:

Improvecoupling flexibilityVSAvoidaxial extension of shifting sleeve

Core Design Contradiction:

Adaptability or versatilityVSLength of moving object

Solution Approach 1:

The patent utilizes the axial dimension efficiently by arranging torque interfaces at different axial positions along the single actuation direction. The shifting sleeve achieves coupling flexibility not by increasing overall length excessively, but by strategically positioning multiple torque interfaces along the axial path, allowing sequential engagement through controlled axial displacement.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS12533947B2Drive train comprising an actuating assembly and a coupling device for coupling an output shaft to a drive and for actuating a parking lock

Publication Date: 2026.01.27 SCHAEFFLER TECHNOLOGIES AG & CO KG

AI summary

The disclosure relates to a drive train of a motor vehicle, the drive train including an actuating device for actuating a coupling device for coupling at least one drive wheel to a drive motor and for coupling the drive wheel to a parking lock unit. A shifting sleeve is provided which displaces in the axial direction and thus can successively connect torque interfaces to one another. This makes it possible to sequentially establish a driving state and a parking state of the drive train.