Workpiece Support Device Reducing Deflection via Segmented Arms
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional roundness measuring devices face accuracy degradation due to workpiece deflection caused by its own weight, especially when supporting large workpieces, and the use of reference planes introduces flatness errors and increased costs.
Innovation Solution
A workpiece supporting device with a horizontal table featuring three first fulcrums and retractable arms with contacting parts distributed around the workpiece's center of gravity, allowing for stable and uniform support by adjusting the positional relation of the fulcrums and arms to minimize deflection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the workpiece is supported at three points by support projections on the table, then the structure is simple, but the distance among support projections must be widened for large workpieces, causing deflection by own weight and degrading roundness measuring accuracy
Solution Approach 1:
The support structure is segmented into multiple independent arms (first arms and second arms) that can be distributed around the workpiece circumference. Each arm is supported by its own fulcrum, allowing the support points to be closely spaced without requiring wide separation, thereby reducing deflection while maintaining structural feasibility
Solution Approach 2:
The support structure transitions from a planar three-point support to a circumferential multi-point support arrangement. The contacting parts are distributed around the workpiece in different directions, effectively utilizing the circular dimension to reduce the distance between adjacent support points and minimize deflection
2Measurement precision
If the workpiece is set on a reference plane such as a surface plate to suppress deflection, then deflection is reduced, but the flatness of the reference plane affects measurement precision and the reference plane becomes large and heavy
Solution Approach 1:
Instead of using a single large reference plane, the support function is segmented into multiple discrete arms with contacting parts distributed around the workpiece. Each arm is supported by its own fulcrum, eliminating the need for a large, heavy reference plane while maintaining support stability and reducing deflection
Solution Approach 2:
The essential support function is extracted from the large reference plane and implemented through multiple small, distributed arms. This removes the unnecessary mass and size of the reference plane while retaining the critical function of supporting the workpiece at multiple points to minimize deflection
3Ease of operation
If the workpiece is set on a reference plane, then support is provided, but it is not possible to determine the contact point, introducing errors in roundness measurement
Solution Approach 1:
The contact interface is segmented into multiple discrete contacting parts (first contacting parts and second contacting parts) distributed around the workpiece. Each contacting part makes contact at a specific, determinable location, eliminating the indeterminacy of contact points while maintaining ease of workpiece support
Solution Approach 2:
The arms are designed to be swingable about fulcrums, providing dynamic adaptability to the workpiece position. This dynamic support mechanism ensures reliable contact at determinable points while accommodating variations in workpiece placement, combining ease of operation with measurement precision
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 solution effectively reduces workpiece deflection at a lower cost by uniformly distributing the weight and allowing for precise contact points, thereby enhancing measurement accuracy and reducing errors in roundness measurements.
Implementation Method 1
the first arm is swingably supported by the first fulcrum; the positional relation between the first fulcrums satisfies a requirement that a first line segment connects two of the three first fulcrums, a second line segment is connectable between the other one first fulcrum and a center of gravity of the workpiece
Implementation Method 2
first arms swingably supported by the respective first fulcrums, each of the first arms swingably supported at a central part in a longitudinal direction of the first arm by the first fulcrum
Data Source
Figure 1
Figure 2
Figure 3
AI summary
There is provided a workpiece supporting device which is able to reduce the deflection of the workpiece at a low cost. A workpiece supporting device for a shape measuring device which measures a shape of a workpiece, includes: a horizontal table; three first fulcrums provided on an upper surface of the table; first arms swingably supported by the respective first fulcrums, each of the first arms swingably supported at a central part in a longitudinal direction of the first arm by the first fulcrum; and a plurality of first contacting parts swingably provided on an upper surface of the first arm for each first fulcrum and distributed from the first fulcrum in different directions, the first contacting parts configured to come into contact with the workpiece.