Throttle Valve Motor Yoke Magnetization for Leakage Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electronic throttle devices, the external exposure of the motor yoke during magnetization can interfere with magnetic sensors and result in an insufficient magnetic circuit due to the physical constraints of the magnetic resin material, leading to magnetic leakage.
Innovation Solution
A throttle valve device design where the motor yoke is assembled within a body, allowing for magnetization after assembly, with a cover and connecting portions that prevent interference and enable proper magnetic circuit formation by maintaining a consistent thickness and spacing between magnets, and using magnetizing yokes for effective magnetization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the motor yoke is resin-molded into a body using magnetic resin material, then the manufacturing process is simplified and costs are reduced, but the magnetic circuit becomes insufficient and magnetic leakage occurs
Solution Approach 1:
The patent uses a composite structure combining magnetic resin material for the motor yoke body with a separate magnetic sheet material (such as permalloy or silicon steel) for the magnetic circuit path. This composite approach allows the benefits of resin molding (simplicity, cost-effectiveness) while compensating for its magnetic limitations through the high-permeability magnetic sheet material that ensures proper magnetic flux circulation and prevents leakage.
2Ease of manufacture
If the motor yoke is exposed externally during magnetization, then the magnetization process is simplified, but magnetic sensors are interfered with and the magnetic circuit is compromised
Solution Approach 1:
The patent introduces a magnetic sheet material as an intermediary component between the magnets and the external environment. This magnetic sheet serves as a mediator that guides and contains the magnetic flux within the intended magnetic circuit path, preventing magnetic field lines from interfering with external magnetic sensors while still allowing the magnets to be magnetized effectively. The magnetic sheet acts as a flux barrier and guide, resolving the conflict between simplified magnetization and sensor protection.
3Stability of the object's composition
If the connecting portion is positioned to connect the motor space to the passage, then the structural integration is improved, but the alignment with magnet spaces may cause magnetic leakage
Solution Approach 1:
The patent applies local quality by differentiating the functional requirements of different regions. The magnetic sheet material is strategically positioned and shaped to cover specific areas where magnetic flux needs to be contained, particularly around the connecting portion that links the motor space to the passage. This localized application of magnetic sheet material ensures that the connecting structure maintains both its structural integration function and its magnetic circuit integrity, preventing leakage at critical junction points.
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 prevents magnetic leakage and ensures a well-formed magnetic circuit, improving the motor's performance and reducing manufacturing costs by allowing for precise positioning and reduced deformation during assembly.
Implementation Method 1
The motor includes a motor yoke made of a magnetic material, a plurality of magnets arranged on an inner circumferential surface of the motor yoke, a motor shaft disposed inside the motor yoke, an armature core coupled to the motor shaft in the motor yoke
Implementation Method 2
The motor includes a motor yoke made of a magnetic material, a plurality of magnets arranged on an inner circumferential surface of the motor yoke
Data Source
AI summary
A throttle valve device includes a body, a valve, a motor, and a cover. The body defines a passage, a motor space, and a connecting portion that connects the motor space to the passage. The motor includes a motor yoke made of a magnetic material, a plurality of magnets that are arranged on an inner circumferential surface of the motor yoke. The plurality of magnets are magnetized in a state where the motor yoke is disposed in the motor space of the body. The plurality of magnets are arranged in a circumferential direction in the motor yoke with a space. The connecting portion is aligned with the space between the plurality of magnets in a radial direction of the motor yoke.