Workpiece Grinding Sequence for Rough-Surface Thickness Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for grinding workpieces with large surface irregularities face difficulties in accurately measuring thickness due to the probe bouncing off the surface, making it challenging to achieve the desired thickness.
Innovation Solution
A method involving a grinding process where the workpiece is held on a chuck table and ground with grindstones while keeping a height gauge measuring element out of contact, followed by measuring the height difference and adjusting the grinding until the surface irregularities fall within a preset range, ensuring accurate thickness measurement and grinding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the probe of a height gauge is held in contact with the surface of the workpiece to measure thickness, then thickness measurement is enabled, but the probe bounces off the surface when large surface irregularities are present, making measurement difficult
Solution Approach 1:
The method performs a preliminary grinding step before thickness measurement to remove surface irregularities. By pre-grinding the workpiece surface to a smoother state, the subsequent thickness measurement with the height gauge probe becomes reliable and accurate, preventing the probe from bouncing off rough surfaces
Solution Approach 2:
The grinding process is divided into multiple stages: a first grinding step for bulk material removal, followed by an intermediate measurement step, and then a second grinding step for precision thickness control. This segmentation allows each stage to optimize for its specific function, with the intermediate measurement providing critical feedback
2Productivity
If continuous grinding is performed to achieve desired thickness, then productivity is improved, but accurate thickness control becomes difficult when surface irregularities cause measurement errors
Solution Approach 1:
The method implements a feedback control loop where thickness is measured after the first grinding step, and the measured values are used to determine whether to proceed to the second grinding step. This feedback mechanism ensures accurate thickness control while maintaining overall productivity by avoiding unnecessary grinding operations
Solution Approach 2:
The grinding process uses periodic measurement and evaluation steps interspersed between grinding operations. Rather than continuous measurement, the system periodically checks thickness at critical transition points, balancing measurement overhead with productivity requirements
3Shape
If the workpiece surface is ground to planarize it, then surface flatness is improved, but the measuring element may still bounce off during subsequent measurement if irregularities remain
Solution Approach 1:
A preliminary grinding step is performed to achieve baseline surface flatness before thickness measurement. This pre-planarization ensures that when the height gauge probe contacts the surface for measurement, the surface is sufficiently smooth to prevent bouncing, enabling accurate height and thickness measurements
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 approach allows for effective planarization of workpieces with surface irregularities by preventing the measuring element from bouncing and enabling continuous grinding until the desired thickness is achieved, ensuring precise measurement and surface flattening.
Implementation Method 1
grinding the surface of the workpiece with grindstones
Implementation Method 2
bringing the measuring element of the height gauge into contact with the surface of the workpiece and measuring a height difference
Data Source
AI summary
A method of grinding a surface of a workpiece that has surface irregularities includes a first grinding step of grinding the surface of the workpiece by a predetermined amount of stock removal while keeping a measuring element of a height gauge out of contact with the surface of the workpiece, thereafter, a height difference measuring step of bringing the measuring element of the height gauge into contact with the surface of the workpiece and measuring a height difference of surface irregularities on the surface of the workpiece with the height gauge, and a second grinding step of, if the measured height difference is larger than a preset range, grinding the surface of the workpiece while keeping the measuring element of the height gauge in contact with the surface of the workpiece until the measured height difference falls within the preset range.