Coaxial Inductive Coil Linear Actuator Position Sensor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing linear actuators for steer-by-wire systems require large installation spaces for measuring devices, necessitating enlarged housings or external placement, which hinders compact design.
Innovation Solution
A linear actuator with a coaxially arranged coil within the housing for inductive position determination of the movable component, utilizing a cylinder coil and coil carrier for compact integration, along with evaluation electronics within the housing to eliminate external connections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional measuring devices are used to determine the position of the movable component, then measurement functionality is achieved, but the housing volume must be enlarged or the measuring device must be located outside the housing
Solution Approach 1:
The coil is arranged coaxially with the linear trajectory of the movable component, allowing the measuring device to be nested within the housing. The coil carrier holds the coil in a position that enables the component to be immersed in the coil during movement, eliminating the need for external placement or housing enlargement.
Solution Approach 2:
The coil is oriented coaxially relative to the linear trajectory of the component, utilizing the spatial dimension along the movement path. This coaxial arrangement allows the measuring device to occupy space efficiently within the housing by aligning with the component's trajectory rather than requiring perpendicular or external positioning.
2Volume of stationary object
If the coil is arranged coaxially with the linear trajectory of the component, then the measuring device can be integrated within the housing, but the coil must be precisely positioned to maintain coaxial alignment
Solution Approach 1:
The coil carrier serves as an intermediary component that holds the coil and provides precise positioning. The coil carrier includes a recess that receives the coil and features a positioning protrusion that aligns with a positioning recess in the housing, ensuring accurate coaxial alignment during assembly.
Solution Approach 2:
The coil carrier is pre-configured with the coil positioned in the correct location before assembly. The positioning features on the coil carrier are designed in advance to ensure that when installed in the housing, the coil achieves the required coaxial alignment, simplifying the assembly process and ensuring manufacturing precision.
3Device complexity
If a single coil is used for position determination, then the structure is simple, but the measurement may be susceptible to external interference
Solution Approach 1:
Two coils are combined to form the measuring device, with both coils arranged coaxially with the linear trajectory of the component. The evaluation electronics receive signals from both coils and perform differential evaluation, combining the information from multiple sources to improve measurement robustness while maintaining relatively simple individual coil structures.
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
Enables a compact design by integrating the measuring device within the housing, reducing space requirements and improving measurement robustness through differential signal evaluation with dual coils.
Implementation Method 1
a coil (11) for inductively determining the position of the component (2)
Data Source
AI summary
A linear actuator for a steer-by-wire system including a component, in particular an axle or a shaft, that can be moved along a linear trajectory, and including a measuring device for determining a position of the component. The measuring device has a coil for inductively determining the position of the component, and the coil is arranged coaxially relative to the linear trajectory of the component.