Magnetic Sensor Unit for Rotation Angle and Stroke Detection

Solution Overview

Problem

Conventional rotation angle detection devices are unable to detect the stroke amount of a detection target that is both rotatable and linearly displaceable, requiring a separate stroke sensor, leading to a complex configuration and increased physical size.

Innovation Solution

A rotation angle and stroke amount detection device that uses a sensor unit with orthogonal magnetic sensing elements to detect changes in the magnetic field, allowing the same signal to be used for both rotation angle and stroke amount calculations, simplifying the configuration and reducing device size.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a separate stroke sensor is added to detect stroke amount in addition to a rotation angle sensor, then both rotation angle and stroke amount can be detected, but the configuration becomes complex and the physical size increases

Engineering Contradiction:

Improvedetection capabilityVSAvoidsensor configuration

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The magnetic sensing elements are designed to perform multiple functions: they detect both the rotation angle and the stroke amount of the detection target using the same sensor unit. The sensor outputs signals that contain information about both rotational position and linear displacement, allowing a single sensor system to provide multiple measurement capabilities without requiring separate sensors for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines the rotation angle detection function and stroke amount detection function into a single integrated sensor unit. By merging these two detection functions into one sensor system that uses magnetic sensing elements, the device achieves both measurement capabilities while reducing the overall complexity and physical size compared to using separate sensors.

Inventive Principle:

Principle #5Merging (Combining)

2Adaptability or versatility

If a separate stroke sensor is added to detect stroke amount in addition to a rotation angle sensor, then both rotation angle and stroke amount can be detected, but the physical size of the detection device increases

Engineering Contradiction:

Improvedetection capabilityVSAvoiddevice size

Core Design Contradiction:

Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The magnetic sensing elements are designed to perform multiple functions: they detect both the rotation angle and the stroke amount of the detection target using the same sensor unit. The sensor outputs signals that contain information about both rotational position and linear displacement, allowing a single sensor system to provide multiple measurement capabilities without requiring separate sensors for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines the rotation angle detection function and stroke amount detection function into a single integrated sensor unit. By merging these two detection functions into one sensor system that uses magnetic sensing elements, the device achieves both measurement capabilities while reducing the overall complexity and physical size compared to using separate sensors.

Inventive Principle:

Principle #5Merging (Combining)

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 device effectively calculates both rotation angle and stroke amount using the same signal from magnetic sensing elements, resulting in a simpler configuration and reduced physical size, while maintaining accurate detection capabilities.

Implementation Method 1

a sensor unit that includes a plurality of magnetic sensing elements detecting changes in a magnetic field generated by a detection target

Methodology Applied

Scientific EffectMagnetic field detection: Magnetic Field

Data Source

PatentUS9709422B2Rotation angle and stroke amount detection device

Publication Date: 2017.07.18 DENSO CORP

AI summary

A rotation angle and stroke amount detection device includes a sensor unit, a rotation angle calculation unit, and a stroke amount calculation unit. The sensor unit includes sin and cos sensors which are magnetic sensing elements that detect changes in a magnetic field caused by rotation or linear displacement of a detection target. The sensor unit outputs sin and cos signals based on detection values of the sin and cos sensors. The rotation angle calculation unit calculates a rotation angle of the detection target based on the sin and cos signals output by the sensor unit. The stroke amount calculation unit calculates a stroke amount of the detection target based on the same signals as those used by the rotation angle calculation unit, i.e., the sin and cos signals. Accordingly, the configuration of the sensor unit may be simplified and the physical size of the device may be reduced.