Two-Part Threaded Spindle with Articulated Coupling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing ball screw designs in vehicles, such as those used in brake systems, are prone to jamming due to misalignment or distortion of the threaded spindle, leading to increased wear and reduced efficiency.

Innovation Solution

A threaded spindle design where the drive part and threaded part are separate components with coupling elements in the form of keyway toothing, allowing for radial offset compensation and absorption of lateral forces, and featuring axially acting stop elements to prevent jamming.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the threaded spindle is designed as a one-piece structure, then the structure is simple, but it is prone to jamming when distorted or misaligned

Engineering Contradiction:
Improvestructure simplicityVSAvoidjamming resistance
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The threaded spindle is divided into two separate parts: a drive part and a threaded part. These parts are connected through coupling elements that allow relative movement, enabling the system to accommodate distortion and misalignment without jamming while maintaining structural simplicity

Inventive Principle:
Principle #1Segmentation

2Loss of energy

If the drive part and threaded part are rigidly connected, then the transmission is efficient, but transverse forces cause jamming when misalignment occurs

Engineering Contradiction:
Improvetransmission efficiencyVSAvoidjamming resistance
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The coupling elements between the drive part and threaded part are designed to allow dynamic adjustment and relative movement. This enables the connection to adapt to misalignment and absorb transverse forces while maintaining efficient power transmission through the threaded mechanism

Inventive Principle:
Principle #15Dynamics

3Loss of energy

If the longitudinal axes are perfectly aligned, then the ball screw drive operates efficiently, but any distortion or misalignment causes jamming and increased wear

Engineering Contradiction:
Improvedrive efficiencyVSAvoidjamming resistance
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The system allows for changes in the relative position and orientation parameters of the drive part and threaded part through the coupling elements. This flexibility enables the drive to maintain efficient operation even when the longitudinal axes are not perfectly aligned, accommodating distortion and misalignment without jamming

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2715188B1Spindle drive
Publication Date: 2019.11.20 SFS INTEC HLDG AG
  • EP2715188B1 patent drawingFigure 1~2
  • EP2715188B1 patent drawingFigure 3~6
  • EP2715188B1 patent drawingFigure 7~10

AI summary

The invention relates to a threaded spindle (11), having a drive part (20), which has a longitudinal axis (A) and is mounted by a first journal (70), and having a threaded part (30), which likewise has a longitudinal axis (B), and having a threaded nut (50), which is mounted by a second journal (80a; 80b) and in which the threaded part (30) is guided. The drive part (20) and the threaded part (30) are formed as separate parts and are each provided with at least one coupling element (25, 55), which are connected to each other in an articulated manner by plugging together. A mutual offset or inclination angle (a) of the longitudinal axes (A, B) of the drive part (20) and of the threaded part (30) can be compensated in this manner. The two-part threaded spindle (11) forms a threaded drive with the threaded nut (50) thereof, which can for example be used in a parking brake of a vehicle braking system. The swinging function created between the drive part (20) and the threaded part (30) reduces transverse forces, which increases efficiency and reduces wear compared to a known threaded drive with a single-part threaded spindle.