Motor Sensor Magnet Integration Reducing Rotational Inertia
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional motors face challenges in reducing size and increasing responsiveness due to the weight of the rotor and the need for a separate mechanism to mount sensor magnets, which increases rotational inertia and complicates miniaturization.
Innovation Solution
The motor design incorporates a sensor magnet mounted in a hollow space of a screw fixing member, allowing it to be integrated with the rotor and reducing rotational inertia, while a detection unit with a hall IC detects the magnetic flux emitted by the sensor magnet, enabling precise rotation sensing without additional sealing processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a separate mechanism is used to mount the sensor magnet on the plate, then the sensor magnet can be securely fixed, but the size of the motor increases and rotational inertia increases
Solution Approach 1:
The sensor magnet is integrated directly into the rotor structure, merging the sensor mounting function with the rotor itself. This eliminates the need for a separate mounting plate and mechanism, thereby reducing motor size while maintaining secure fixation of the sensor magnet through direct integration.
Solution Approach 2:
The rotor is designed to serve multiple functions: it provides the rotating component for motor operation and simultaneously serves as the mounting structure for the sensor magnet. This multi-functionality reduces the overall number of components needed in the system.
2Reliability
If a separate mechanism is used to mount the sensor magnet on the plate, then the sensor magnet can be securely fixed, but rotational inertia increases and responsiveness decreases
Solution Approach 1:
By merging the sensor magnet mounting function directly into the rotor, the design eliminates additional mounting components that would increase rotational inertia. The sensor magnet becomes an integral part of the rotor assembly, minimizing the mass that needs to be accelerated during rotation.
Solution Approach 2:
The separate mounting plate and mechanism are extracted from the system, removing unnecessary mass from the rotating assembly. Only the essential sensor magnet remains integrated with the rotor, reducing rotational inertia while maintaining secure fixation.
3Measurement precision
If the sensor magnet is mounted on a separate plate, then the sensor can detect rotation, but additional sealing processes are required
Solution Approach 1:
The sensor magnet and rotor are merged into a single integrated assembly, eliminating the need for separate sealing between the magnet mounting plate and rotor. This integration simplifies the sealing requirements while maintaining the detection function.
Solution Approach 2:
The separate mounting plate that would require additional sealing interfaces is extracted from the design. The sensor magnet is mounted directly on the rotor, removing the intermediate sealing layer and simplifying the overall structure.
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
This design minimizes motor size, reduces rotational inertia, and enhances responsiveness by integrating the sensor magnet with the rotor, allowing for precise rotational angle detection and increased assembly flexibility.
Implementation Method 1
The sensor magnet may be mounted on a plate disposed over the rotor, and emits a magnetic flux or a polarity according to rotation of the rotor section
Implementation Method 2
The hall IC is disposed to be opposite to the sensor magnet, and detects the magnetic flux or the polarity emitted from the sensor magnet to detect rotation of the rotor
Data Source
Figure 1
Figure 2
AI summary
Provided is a motor including a rotor section including a rotor core, a drive magnet attached to the rotor core, and a screw disposed in the rotor core and rotated with the rotor core; a nut member coupled to the screw and vertically moved upon rotation of the rotor section; a stator section disposed to be opposite to the rotor section; a sensor magnet disposed under the screw; and a circuit board on which a magnetic device disposed to be opposite to the sensor magnet is mounted.