Vehicle Flap Spindle Drive with Dual-Axis Nut Support

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing drive devices for vehicle flaps require large installation spaces due to complex spindle nut designs and inadequate bearing assemblies, leading to insufficient support and potential damage from excessive axial loads.

Innovation Solution

A drive device with a compact design featuring a spindle nut supported by a bearing assembly allowing rotation around two perpendicular axes, coupled with a clutch assembly to decouple from excessive loads, and a coupling assembly for reliable force transmission and misalignment compensation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a complex spindle nut design is used to support rotation around two perpendicular axes, then the bearing capacity and reliability are improved, but the installation space requirement increases

Engineering Contradiction:
Improvespindle nut support reliabilityVSAvoidinstallation space
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The bearing assembly is segmented into a first bearing element supporting rotation around the first rotation axis and a second bearing element supporting rotation around the second rotation axis. This segmentation allows each bearing element to be optimized for its specific function while reducing the overall space requirement compared to a single complex bearing structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention utilizes two perpendicular rotation axes (first rotation axis and second rotation axis) to enable the spindle nut to compensate for misalignments in multiple dimensions. By arranging bearing elements along different axes, the system achieves enhanced reliability and misalignment compensation without requiring a large single-dimensional space.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If a bearing assembly with two bearing elements is used to support the spindle nut, then the misalignment compensation capability is improved, but the device complexity increases

Engineering Contradiction:
Improvemisalignment compensation capabilityVSAvoidbearing assembly complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The first and second bearing elements serve multiple functions: they support the spindle nut, enable rotation around perpendicular axes, and compensate for misalignments between the actuator housing and the flap. This multi-functionality reduces the need for additional separate components, thereby limiting the increase in device complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The bearing elements act as intermediaries between the actuator housing and the spindle nut, absorbing misalignments and enabling smooth rotational movement. This intermediary function protects the drive assembly from excessive axial loads while maintaining a relatively simple overall structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Device complexity

If the spindle nut is directly supported by the actuator housing, then the device complexity is reduced, but the axial load protection capability is insufficient

Engineering Contradiction:
Improvesupport structure complexityVSAvoidaxial load protection capability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The bearing elements are introduced as intermediary components between the actuator housing and the spindle nut. These intermediaries provide the necessary support and protection against excessive axial loads while maintaining a relatively simple structure. The bearing elements absorb misalignments and prevent direct transmission of harmful loads to the drive assembly.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The bearing elements are pre-installed to cushion and absorb excessive axial loads before they can reach the drive assembly. This beforehand cushioning protects the spindle nut and drive assembly from damage while maintaining a simple overall structure without requiring complex protection mechanisms.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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 solution provides a more flexible and compact drive device that effectively supports the spindle nut, reduces installation space, and protects the drive assembly from damage by decoupling under excessive loads, ensuring reliable operation and reduced maintenance.

Implementation Method 1

a bearing assembly comprising a first bearing element and a second bearing element which allow the spindle nut to rotate around a first rotation axis and around a second rotation axis

Methodology Applied
Scientific EffectRolling contact bearing: Ball Bearing

Implementation Method 2

the coupling assembly comprises a first coupling element and a second coupling element which enclose a clutch assembly

Methodology Applied
Scientific EffectFriction clutch: Friction

Implementation Method 3

A worm wheel is connected to an end of a driving shaft of the drive assembly, wherein the worm wheel engages with an outer thread of the spindle nut for coupling the drive assembly to the actuator assembly

Methodology Applied
Scientific EffectWorm drive: Worm Drive

Implementation Method 4

the actuator assembly comprises a spindle extending through the actuator housing defining a spindle axis and a spindle nut, wherein the spindle extends through and engages with the spindle nut

Methodology Applied
Scientific EffectScrew mechanism: Screw

Data Source

PatentEP3828371B1Drive device
Publication Date: 2024.07.03 EDSCHA ENG GMBH
  • EP3828371B1 patent drawingFigure 1~2
  • EP3828371B1 patent drawingFigure 3

AI summary

The invention relates to a drive device, particularly for driving a flap, comprising an actuator housing (2) with an open cavity (7), wherein the actuator housing (2) is connectable to one of a flap and a vehicle body, an actuator assembly (8) enclosed at least in part by the actuator housing (2), wherein the actuator assembly (8) comprises a spindle (9) extending through the actuator housing (2) and defining a spindle axis (S), wherein the spindle (9) is connectable to the other one of the door and the vehicle body, and a spindle nut (10), wherein the spindle (9) extends through and engages with the spindle nut (10), a drive assembly (6) to drive the actuator assembly (8), and a bearing assembly (11), which bearing assembly (11) comprises a first bearing element (12) which allows the spindle nut (10) to rotate around a first rotation axis (X) and around a second rotation axis (Y), wherein the first rotation axis (X) and the second rotation axis (Y) are perpendicular to each other and the spindle axis (S). It is the object of the invention to provide a drive device that is more flexible in terms of use in any kinematic of a door and has a compact size. The object is achieved by a drive device characterised in that a first end (10a) of the spindle nut (10) is connected to the first bearing element (12), and that an outer surface (12a) of the first bearing element (12) facing away from the spindle nut (10) slidingly abuts against an inner wall (7a) of the open cavity (7).