Linear Conveyor Slider Magnetic Scale Thermal Expansion Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing magnetic linear scales in linear conveyers face errors in position detection due to thermal expansion differences between plastic magnets and back yokes, leading to warping and position gaps when the slider is moved between different temperature environments.
Innovation Solution
The use of a plastic magnet with a fixed portion and a movable portion relative to the back yoke, where the movable portion is held by band members, ensures that the magnetic scale maintains its position accuracy across temperature changes by allowing the plastic magnet to deform and return to its original position relative to the back yoke.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If a plastic magnet is used in the magnetic scale, then the weight of the slider is reduced, but position detection errors occur due to thermal expansion differences between the plastic magnet and back yoke
Solution Approach 1:
The plastic magnet is divided into a fixed portion that is bonded to the back yoke and a movable portion that can deform independently. This segmentation allows the magnet to accommodate thermal expansion differences between the plastic material and the back yoke, preventing position detection errors while maintaining weight reduction benefits
Solution Approach 2:
The invention changes the physical state and configuration of the plastic magnet by creating a fixed portion and a movable portion with different bonding states. The movable portion can change its position relative to the back yoke in response to temperature changes, accommodating thermal expansion parameter changes without causing detection errors
2Stability of the object's composition
If the plastic magnet is rigidly fixed to the back yoke, then position stability is improved, but thermal expansion differences cause warping and position gaps
Solution Approach 1:
The plastic magnet is segmented into a fixed portion bonded to the back yoke and a movable portion that can deform independently. This segmentation resolves the contradiction by providing both stability (through the fixed portion) and thermal accommodation (through the movable portion), preventing warping and position gaps
Solution Approach 2:
The invention introduces dynamic characteristics to the previously static magnet structure. The movable portion of the plastic magnet can dynamically adjust its position in response to thermal expansion, allowing the system to maintain alignment precision under varying temperature conditions
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 configuration reduces the likelihood of errors in detecting the slider's position and minimizes weight while maintaining precision, as the plastic magnet's deformation matches the back yoke's expansion and contraction, maintaining alignment and reducing the need for additional bonding materials.
Implementation Method 1
the plastic magnet's deformation matches the back yoke's expansion and contraction, maintaining alignment
Implementation Method 2
a magnetic linear scale that detects a position of the slider according to magnetic flux from the magnetic scale
Implementation Method 3
the plastic magnet's deformation matches the back yoke's expansion and contraction
Data Source
AI summary
A linear conveyer includes a stationary module and a slider. The stationary module includes a frame extending linearly, a stator including armature coils and fixed to the frame, a rail, and a magnetic sensor. The slider movable along the rail with a driving linear motor includes magnetic poles, a rail guide fitted on the rail, and a magnetic scale. The magnetic scale includes a plastic magnet having magnetic poles and extending along an extending direction in which the rail extends, and a back yoke where the plastic magnet is placed. A position of the slider is detected by the magnetic sensor and the magnetic scale. The plastic magnet has a fixed portion that is fixed with respect to the back yoke and a portion other than the fixed portion, the portion being movable relative to the back yoke along an extending direction in which the magnetic scale extends.