Sheet Material Dispenser Cutting Mechanism to Prevent Tabbing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sheet material dispensers require a high pull force to initiate a dispense cycle, leading to issues like 'tabbing' and excessive material usage, and lack the ability to adjust the tail length for user convenience and conservation.
Innovation Solution
The dispenser features a cutting mechanism with a serrated blade and blade carrier that reduces the required pull force and includes a tail length adjustment mechanism, allowing for customizable tail length and encouraging single-sheet usage through a controlled dispense cycle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a high spring force is used to power the drive roller and cutting mechanism, then the sheet material can be fully or partially severed to provide a single sheet, but the pull force required to initiate a dispense cycle increases to two pounds or more
Solution Approach 1:
The cutting mechanism is segmented into a cutting blade and a stationary tear bar. The cutting blade partially severs the sheet material web, and the stationary tear bar completes the severing action. This segmentation allows the spring force to be reduced while still achieving complete sheet separation, thereby reducing the pull force required to initiate a dispense cycle.
Solution Approach 2:
A stationary tear bar is introduced as an intermediary element. The drive roller carries a cutting blade that partially cuts the web, and the stationary tear bar positioned adjacent to the drive roller completes the cut. This intermediary structure distributes the cutting action, reducing the force requirement on the spring mechanism.
2Force
If a high pull force is required to initiate a dispense cycle, then the drive roller can be rotated to power the cutting mechanism, but tabbing occurs where a small portion of the sheet material tail tears off in the user's hand
Solution Approach 1:
The cutting action is segmented between a movable cutting blade on the drive roller and a stationary tear bar. This segmentation allows for a more controlled cutting process that reduces the risk of tabbing by ensuring the web is cleanly separated at the intended location rather than tearing unpredictably in the user's hand.
Solution Approach 2:
The cutting mechanism is designed to automatically complete the cutting action as the drive roller rotates. The stationary tear bar works in conjunction with the cutting blade to automatically finish the severing process without requiring additional user force or manipulation, thereby preventing tabbing.
3Productivity
If the dispenser allows repeated and immediate cycling to dispense multiple sheets, then user needs are met, but sheet material conservation is compromised leading to excessive use and waste
Solution Approach 1:
The dispenser incorporates a control system that provides feedback to limit the frequency of dispense cycles. The microprocessor monitors and controls the operation of the drive roller and cutting mechanism, preventing repeated immediate cycling and encouraging single-sheet usage to promote material conservation.
Solution Approach 2:
The dispenser is designed to enforce periodic action by limiting the frequency of dispense cycles. The control system introduces time intervals between cycles, preventing continuous rapid dispensing and promoting more deliberate, conservation-oriented usage patterns.
4Device complexity
If the tail length is fixed, then the dispenser structure is simple, but the tail may be inadequate for users to grip or too long causing excessive material use
Solution Approach 1:
The tail length is made dynamic and adjustable rather than fixed. The dispenser incorporates a tail length adjustment mechanism that allows the attendant to set the length of the tail extending from the dispenser housing. This dynamic adjustment capability enables optimization of tail length for different user needs and dispenser locations while maintaining reasonable structural complexity.
Data Source
AI summary
Apparatus for dispensing sheet material from a sheet material dispenser are described. Dispenser embodiments include drive and tension rollers supported within a housing forming a nip therebetween. Pulling of sheet material through the nip and against the drive roller rotates the drive roller. Dispenser embodiments may include a cutting mechanism powered by drive roller rotation with an improved carrier-supported blade permitting highly-efficient dispenser operation. Dispenser embodiments may include a sheet material tail length adjuster which permits the attendant to shorten or lengthen the tail length extending away from the dispenser. Dispenser embodiments may further include a sheet material conservation feature which imposes a delay between dispense cycles encouraging use of a single sheet of material and discouraging sheet material waste.