Axial Nested Linear Actuator Redundancy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing linear actuators for hydraulic or pneumatic systems, such as brake systems, are prone to failure due to single errors like ball screw blockages and require significant installation space, making them unsuitable for compact applications like autonomous vehicles.
Innovation Solution
A compact linear actuator design with redundant motorized drive units and rotation-translation gears arranged axially, ensuring full functionality even if one component fails, and integrating the components into a hydraulic or pneumatic block for space efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a simple linear actuator with a single drive unit is used, then the device complexity is low, but the reliability is insufficient because a single error causes complete failure
Solution Approach 1:
The linear actuator is divided into two independent drive units, each with its own motor and rotation-translation gear. This segmentation allows the system to maintain functionality even if one drive unit fails, as the other unit can continue to operate independently to provide the required linear actuating force.
Solution Approach 2:
Each drive unit is designed with specific local characteristics - the first drive unit has a hollow drive shaft that allows the second drive unit to be arranged axially within or around it. This local structural quality enables compact integration while maintaining the independence of each drive unit for fault tolerance.
2Reliability
If two drive units are arranged axially parallel to each other, then the reliability is improved through redundancy, but the installation space requirement increases significantly
Solution Approach 1:
The second drive unit is arranged axially within or around the first drive unit, with the second motor's drive shaft passing through the hollow drive shaft of the first motor. This nested arrangement allows both drive units to occupy the same axial space, significantly reducing the overall installation footprint while maintaining the redundancy needed for high reliability.
Solution Approach 2:
Instead of arranging the two drive units side-by-side in a planar configuration, the invention uses axial arrangement along the length of the hollow drive shaft, utilizing the third dimension (axial direction) to pack the redundant components more efficiently. This dimensional reorganization reduces the lateral space requirement while maintaining functional independence.
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 design maintains high functional reliability with minimal space requirements, allowing the actuator to remain operational in case of single errors and integrate seamlessly into vehicle systems.
Implementation Method 1
a first rotation-translation gear driven by the first motor drive unit with a first threaded spindle and a first threaded nut engaging with the threaded spindle
Data Source
Figure 1
AI summary
The invention relates to a linear actuator (1) for generating a linear actuating force, comprising a first drive unit (10) having a first drive shaft (11) designed as a hollow shaft, a first rotation-translation transmission (20) driven by the first drive unit (10), having a first threaded spindle (21) and a first threaded nut (22) engaging with the threaded spindle, wherein the drive shaft (11) of the first drive unit (10) is designed as a first threaded spindle (21), a second drive unit (30) arranged axially to the first drive unit (10) and having a drive shaft (31), and a second rotation-translation transmission (40) driven by the second drive unit (30), having a second threaded spindle (41) and a threaded nut (42) engaging with the second threaded spindle (41), wherein the drive shaft (31) of the second drive unit (30) is connected to the second threaded spindle (41) via the hollow shaft (11) in a rotationally fixed manner.