Single-Piece Snap-Off Blade Dispenser for Utility Knives

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing snap-off blade dispenser systems require assembly and are not designed to be easily integrated into snap-off blade utility knives, with complex mechanisms for blade replacement that can be cumbersome and require reassembly when empty.

Innovation Solution

A single-piece snap-off blade dispenser system with a blade extraction opening height corresponding to the thickness of one blade, allowing for easy dispensing with a one-touch action, made from plastic materials like polypropylene or ABS, featuring an elevated ridge and elastic elements for alignment and safety chamfered corners for user protection, which can be easily integrated into a snap-off knife without assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple parts are assembled to create a blade dispenser system, then the functionality and reliability are improved, but the device complexity and manufacturing cost increase

Engineering Contradiction:
Improveblade dispenser functionalityVSAvoidnumber of parts
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges multiple functional components (case, spring member, pushbar, blade guiding features) into a single integrated dispenser body made from one piece of material. This eliminates the need for separate parts and assembly operations while maintaining all necessary functions for blade storage, pushing, and extraction.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The single-piece dispenser structure performs multiple functions simultaneously: it stores multiple blades, provides elastic pushing force via an integrated spring member, guides blade extraction through built-in guiding features, and prevents accidental activation. All these functions are achieved within one monolithic component rather than through separate assembled parts.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Reliability

If a complex mechanism with multiple parts is used, then the blade dispensing reliability is improved, but the ease of manufacture deteriorates

Engineering Contradiction:
Improveblade dispensing reliabilityVSAvoidassembly requirement
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The case, spring member, pushbar, and blade guiding features are combined into a single monolithic structure that can be manufactured as one piece using injection molding or similar processes. This eliminates assembly operations entirely while maintaining the reliable mechanical interactions between components that would otherwise require precise fitting and assembly.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The dispenser is designed as a self-contained unit where all components are permanently integrated and require no assembly or disassembly by the user. The system serves itself by having the spring member automatically push blades forward and the guiding features automatically align blades for extraction, eliminating the need for user intervention in assembly or operation.

Inventive Principle:
Principle #25Self-service

3Ease of operation

If the blade extraction opening height is increased, then the ease of operation is improved, but the manufacturing precision requirement increases to ensure only one blade extracts at a time

Engineering Contradiction:
Improveblade extraction easeVSAvoidopening height tolerance
Core Design Contradiction:
Ease of operationVSManufacturing precision

Solution Approach 1:

The dispenser incorporates localized blade thickness indicators or color-coded markings at specific positions along the blade length. These local visual cues guide the user to grasp and extract the correct portion of the blade, ensuring that only one blade thickness is removed at a time without requiring tight tolerances on the extraction opening dimensions.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The blade guiding features or extraction opening area incorporate color-coded indicators that change or differ in color to visually signal the correct extraction depth. This visual feedback mechanism ensures users extract exactly one blade thickness without needing precision-engineered opening dimensions, as the color change provides real-time guidance during the extraction operation.

Inventive Principle:
Principle #32Color changes

4Adaptability or versatility

If traditional multi-part dispenser systems are used, then the adaptability to different knife models is improved, but the loss of time for assembly and disassembly increases

Engineering Contradiction:
Improveknife model compatibilityVSAvoidassembly time
Core Design Contradiction:
Adaptability or versatilityVSLoss of time

Solution Approach 1:

The dispenser is designed as a single-piece unit that can be quickly installed or removed as one component, eliminating the time-consuming assembly and disassembly of multiple parts. The integrated structure maintains adaptability to different knife models through standardized mounting interfaces while reducing the time penalty associated with part consolidation.

Inventive Principle:
Principle #5Merging (Combining)

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

Facilitates simple, cost-effective, and safe blade replacement by allowing one-touch dispensing and removal of blades outside the knife, reducing manufacturing complexity and user risk, while eliminating the need for assembly and complex mechanisms.

Implementation Method 1

The back wall portion may comprise at least one elastic element adapted to push the stacked snap-off blades towards said one or more front wall portions

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3213888B1Snap-off blade dispenser system
Publication Date: 2019.08.07 HULTAFORS GROUP AB
  • EP3213888B1 patent drawingFigure 1
  • EP3213888B1 patent drawingFigure 2
  • EP3213888B1 patent drawingFigure 3a~3c

AI summary

The present invention relates to system comprising a snap-off blade dispenser (10) and a plurality of snap-off blades (12), wherein the dispenser is fittable inside a snap-off knife (66), and wherein the dispenser is made in one piece and comprises: a back wall portion (14); a pair of opposing side wall portions (16a-b); and an elongated compartment (20) adapted to accommodate the plurality of snap-off blades (12) in a stacked configuration, wherein the elongated compartment at one end thereof has a blade extraction opening (28), the height of the blade extraction opening substantially corresponding to the thickness of one of said blades, and wherein the back wall portion comprises a resiliently arranged abutment (36) adapted to engage an opening (26) in each of the stacked blades.