Sheet Dispenser Cutting Mechanism for Low Pull Force Dispensing
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 patent removes the spring-powered drive mechanism entirely, extracting the harmful high-force element from the system. The drive roller is now powered solely by user pull force without spring assistance, eliminating the need to overcome high spring force during initiation.
Solution Approach 2:
The patent replaces the spring-powered mechanical drive system with a direct pull-driven system. The cutting mechanism is also modified to use a rotary blade that cuts during the deceleration phase of the drive roller, substituting the spring-assist mechanical system with a friction-based direct drive system.
2Productivity
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 patent extracts the spring-powered drive mechanism that causes high pull force requirements, eliminating the root cause of tabbing. The friction-based direct drive system allows gradual acceleration without sudden force spikes that tear the tail.
Solution Approach 2:
The patent changes the operational parameters of the drive roller from spring-powered high-force operation to friction-based low-force operation. The cutting mechanism timing is also changed to occur during deceleration rather than during high-force acceleration, preventing tabbing.
3Adaptability or versatility
If the dispenser allows repeated and immediate cycling to dispense multiple sheets, then user needs are met, but excessive use of sheet material occurs increasing cost and waste
Solution Approach 1:
The patent implements a mandatory pause period between dispense cycles through the tail length adjustment mechanism. The extended tail length naturally encourages users to take their time and use only one sheet at a time, creating a periodic usage pattern that prevents excessive cycling and material waste.
4Device complexity
If the tail length is fixed, then the dispenser structure is simple, but the tail may be too short for users to grasp easily or too long encouraging excessive material use
Solution Approach 1:
The patent makes the tail length dynamic and adjustable rather than fixed. The tail length adjustment mechanism allows the dispenser to adapt to different user needs and installation locations, optimizing ease of operation without requiring complex electronic controls.
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 minimizes 'tabbing' and excessive material usage by reducing the pull force needed to dispense a sheet, enabling the use of lightweight materials and allowing for adjustable tail lengths, promoting conservation and user convenience.
Implementation Method 1
a cutting mechanism including a serrated blade and a blade carrier... the serrated blade cuts the sheet material web
Implementation Method 2
pulling of the sheet material through the nip and against the body rotates the drive roller
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Apparatus for dispensing sheet material from a sheet material dispenser (10) are described. Dispenser embodiments include drive (19) and tension rollers (17) supported within a housing (11) forming a nip (79) therebetween. Pulling of sheet material (29) through the nip (79) and against the drive roller (19) rotates the drive roller. Dispenser embodiments may include a cutting mechanism (61) powered by drive roller (19) rotation with an improved carrier-supported (103) blade (101) permitting highly-efficient dispenser operation. Dispenser embodiments may include a sheet material tail length adjuster (23) which permits the attendant to shorten or lengthen the tail (30) length extending away from the dispenser. Dispenser embodiments may further include a sheet material conservation feature (21) which imposes a delay between dispense cycles encouraging use of a single sheet of material and discouraging sheet material waste.