Dwell Area Buffering for Sheet Grammage Consistency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sheet manufacturing apparatuses using the dry method face variations in grammage due to fluctuations in the amount of raw material supplied, leading to inconsistent sheet production.
Innovation Solution
Incorporating a dwell area between the supply port and opening ports in the deposition unit allows the defibrated material to temporarily dwell, absorbing variations in supply amount and reducing grammage fluctuations, with the dwell area retaining 30% to 80% of the defibrated material's volume or mass, thereby stabilizing the sheet production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by stationary object
If a dry method is used for sheet manufacturing to reduce apparatus size and energy consumption, then the apparatus size and energy use are reduced, but the grammage of produced sheet varies depending on the amount of raw material supplied
Solution Approach 1:
The patent introduces a dwell area that temporarily stores defibrated material before it is supplied to the deposition unit. This preliminary storage action allows the system to buffer variations in raw material supply, ensuring consistent material flow to the deposition unit regardless of upstream fluctuations, thereby maintaining grammage consistency while using energy-efficient dry method processing
2Adaptability or versatility
If the amount of raw material supplied at the upstream end varies, then flexibility in material supply is improved, but the grammage of produced sheet becomes inconsistent
Solution Approach 1:
The dwell area acts as an intermediary between the upstream material supply and the deposition unit. It decouples the upstream supply variations from the deposition process, allowing flexible material supply upstream while maintaining consistent grammage at the deposition unit by regulating material flow through the intermediate storage buffer
Data Source
AI summary
A sheet manufacturing apparatus of the present invention includes a defibrating unit that defibrates a material containing fibers into a defibrated material, and a deposition unit that deposits a defibrated material defibrated by the defibrating unit. The deposition unit includes a material supply port through which the defibrated material from the defibrating unit is supplied, a plurality of opening ports through which the supplied defibrated material passes, and a dwell area disposed between the material supply port and the opening ports so that the defibrated material temporarily dwells in the dwell area. The dwell area allows the defibrated material to temporarily dwell in the dwell area so that a variation amount of the defibrated material that passes through the opening ports becomes smaller than a variation amount of the defibrated material supplied through the material supply port.