Glass Sheet Bending Accuracy via Segmented Roller Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for bending glass sheets along both conveying and perpendicular directions suffer from reduced accuracy due to uneven contact with curving rollers, leading to deformation and bowing, which compromises the bending process.
Innovation Solution
A method and apparatus where the glass sheet is first bent along the conveying direction using up-down moving rollers, then nipped by upper and lower curving rollers to maintain the shape while being bent along the perpendicular direction, ensuring high accuracy by controlling the curvature and using a combination of straight and curving rollers for precise shaping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If heated compressed air is blown to press the glass sheet against curving rollers to bend it along the perpendicular direction, then the glass sheet can be bent along the perpendicular direction, but the glass sheet is not uniformly contacted by the curving rollers causing deformation and bowing that deteriorates bending accuracy
Solution Approach 1:
The forming process is divided into two distinct stages: first bending along the conveying direction using up-down moving rollers, then bending along the perpendicular direction using curving rollers. This segmentation allows each bending operation to be optimized independently, ensuring uniform contact and high accuracy for each direction without interference from the other bending operations.
Solution Approach 2:
The glass sheet is first bent along the conveying direction and has its shape fixed before the second bending operation along the perpendicular direction. This preliminary action ensures that the glass sheet maintains its curved shape from the first bending operation during the second operation, preventing deformation and bowing, and achieving high bending accuracy in both directions.
2Manufacturing precision
If the glass sheet is bent along the conveying direction first and then along the perpendicular direction, then high forming accuracy can be achieved, but the process time increases
Solution Approach 1:
The glass sheet is continuously conveyed through both bending operations without interruption. The first bending operation along the conveying direction is performed while the sheet moves on the roller conveyer, and the second bending operation along the perpendicular direction is performed subsequently while still on the same conveyer system. This continuous processing eliminates idle time between operations and maintains high productivity while achieving high forming accuracy.
3Shape
If curving rollers are used to bend the glass sheet along the perpendicular direction, then the glass sheet can be shaped, but uneven contact between the glass sheet and curving rollers causes wrinkles and temperature drop
Solution Approach 1:
The bending process is segmented into two directional operations with different roller configurations. The first operation uses up-down moving rollers for bending along the conveying direction, and the second operation uses curving rollers for bending along the perpendicular direction. This segmentation ensures that each operation is optimized for its specific direction, preventing wrinkles and temperature drop while achieving the desired curved shape.
Solution Approach 2:
The glass sheet is first formed into the correct shape and temperature distribution along the conveying direction before undergoing the perpendicular direction bending. This preliminary action ensures that the glass sheet is in the optimal state for the second operation, preventing wrinkles and temperature drop during the curving roller operation and maintaining high surface quality.
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 enhances forming accuracy and productivity by maintaining the curved shape along the conveying direction while achieving precise bending along the perpendicular direction, reducing wrinkles and temperature drop during the process, thus producing high-quality tempered glass.
Implementation Method 1
the glass sheet is bent in the conveying direction by its own weight so as to fit to the curved surface formed on the conveying surface
Implementation Method 2
a heated compressed air is blown from air blowing means to the glass sheet. In this case, the glass sheet is pressed against the curving rollers by the heated compressed air
Data Source
Figure 1
Figure 2~3(E)
Figure 4~5(B)
AI summary
The present invention relates to a method and an apparatus for bending a glass sheet, and has an object of achieving high forming accuracy of a glass sheet along a perpendicular direction perpendicular to a conveying direction of the glass sheet, in particular, to obtain high forming accuracy both along the conveying direction and the perpendicular direction. An apparatus 10 for bending a glass sheet for bending a heated glass sheet G while the glass sheet G is conveyed in a conveying direction X by a roller conveyer 18, 20 comprising a plurality of conveying rollers; the apparatus 10 comprising a plurality of straight rollers that are arranged upper and lower positions across a conveying surface for the glass sheet G and not curved on the conveying surface, and a plurality of curving rollers 36 arranged upper and lower positions across the conveying surface for the glass sheet G on adjacently downstream side of the straight rollers 34 and curvable along a perpendicular direction Y in the conveying surface so as to bend the glass sheet G along the perpendicular direction Y.