Coaxial Hollow-Shaft Torque and Angle Measurement Layout

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing systems for determining torque and rotary angle between shafts coupled via a gear mechanism are complex and costly due to the need for multiple sensors and separate rotary angle measuring systems.

Innovation Solution

A device where one shaft is designed as a hollow shaft, allowing the second shaft to be coaxially arranged inside, with measurement standards at the same end that can be scanned by sensors, enabling simultaneous determination of torque and rotary angle without additional mechanical components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a second rotary angle measuring system is arranged on the output shaft to detect actual movement, then rotary angle position accuracy is improved, but device complexity increases due to requiring additional sensors and measurement systems

Engineering Contradiction:

Improverotary angle position accuracyVSAvoidnumber of sensors and measurement systems

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent combines two separate rotary angle measuring systems into a single integrated device. The first sensor detects the rotary angle of the input shaft, while the second sensor detects the rotary angle of the output shaft, both within one unified measurement device. This merging reduces device complexity while maintaining the ability to accurately measure both shaft positions and calculate torque through their angular difference.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements a nested structure where the second shaft (output shaft) is arranged coaxially inside the first shaft (input shaft). The measurement standards are positioned such that both sensors can scan their respective standards simultaneously within a compact arrangement. This nesting reduces the overall device size and simplifies the structure while enabling dual shaft measurement.

Inventive Principle:

Principle #7Nested doll (Nesting)

2Measurement precision

If additional sensors such as strain gauges are used to determine torque, then torque measurement capability is improved, but manufacturing cost increases

Engineering Contradiction:

Improvetorque measurement capabilityVSAvoidmanufacturing cost

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent replaces mechanical strain gauge-based torque measurement with an optical sensing system. By using two optical sensors to detect the angular positions of the input and output shafts, and calculating torque from the angular difference between them, the system eliminates the need for expensive strain gauges while maintaining torque measurement capability.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The measurement device performs multiple functions: it measures the rotary angle of the input shaft, measures the rotary angle of the output shaft, and calculates torque based on the angular difference between the two shafts. This multi-functionality is achieved within a single integrated device using only two optical sensors, reducing overall system cost while providing comprehensive measurement capabilities.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Measurement precision

If two spatially separate rotary angle measuring systems are used, then measurement accuracy is improved, but device complexity and space requirements increase

Engineering Contradiction:

Improverotary angle measurement accuracyVSAvoidstructural complexity and spatial arrangement

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent merges two separate rotary angle measuring systems into one integrated device. Both sensors and their corresponding measurement standards are arranged within a single device structure, eliminating the need for two spatially separate systems. This reduces structural complexity while maintaining the ability to accurately measure both shaft angles simultaneously.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent uses a nested arrangement where the output shaft is positioned inside the input shaft, and both measurement standards are accessible from the same end of the assembly. This allows both sensors to be mounted in close proximity, scanning their respective standards simultaneously within a compact space, thereby reducing device complexity and spatial requirements.

Inventive Principle:

Principle #7Nested doll (Nesting)

Data Source

PatentUS12235176B2Device for determining the torque and/or rotational angle between a first shaft and a second shaft

Publication Date: 2025.02.25 NEURA ROBOTICS GMBH

AI summary

A device for determines the torque and/or the rotary angle between a first shaft and a second shaft, which are coupled via a gear mechanism to rotate relative to one another about an axis of rotation. The first shaft has a first end region, a second end region, and a first direction vector pointing in parallel with the axis of rotation from the first end region to the second end region, and the second shaft has a first end region, a second end region, and a second direction vector pointing in parallel with the axis of rotation from the first end region to the second end region. The first shaft is designed as a hollow shaft and the second shaft is arranged coaxially in the first shaft in such a way that the first direction vector and the second direction vector have the same orientation.