Stapling Device Eyelet Support Timing for Thin Paper

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

When using eyelet staples in stapling devices, thin paper products often deform due to insufficient support during the stapling process, leading to 'collapse' of the eyelet as the staple legs are bent, especially when multiple layers of thin sheets are stapled, as they cannot withstand transverse forces effectively.

Innovation Solution

The staple support is only withdrawn from the ring eyelet area once the staple legs are largely bent over, ensuring that no harmful lateral forces occur that could cause deformation, achieved through mechanical, electrical, or electronic coupling with the stapling device's movement, or using a cam to effect this withdrawal shortly before the bottom dead center of the stapling movement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the staple support is withdrawn early from the ring eyelet area, then the stapling process can proceed efficiently, but the eyelet deforms and collapses due to lateral forces during staple leg bending

Engineering Contradiction:
Improvestapling process efficiencyVSAvoideyelet geometry precision
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The staple support remains in position during the initial driving phase to prevent eyelet deformation, and is withdrawn only after the staple legs are largely bent over, ensuring the eyelet is already stabilized by the bent legs before the support is removed

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The staple support's position is dynamically adjusted based on the stapling process stage - it remains stationary during driving to support the eyelet, then is withdrawn after bending begins, with its position controlled by the driver's movement relative to the staple support's lower end

Inventive Principle:
Principle #15Dynamics

2Reliability

If the staple support remains in the ring eyelet area throughout the bending process, then the eyelet is continuously supported, but it cannot be released in time for subsequent processing

Engineering Contradiction:
Improveeyelet support stabilityVSAvoidstaple support retraction timing
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The staple support's withdrawal is controlled by feedback from the driver's position - the driver's lower edge passing the staple support's lower end opposite the sheet-like material serves as the trigger signal for the staple support to begin its rearward movement

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The driver's movement automatically controls the staple support's withdrawal timing through mechanical coupling or cam mechanism, eliminating the need for separate control systems

Inventive Principle:
Principle #25Self-service

3Productivity

If multiple layers of thin sheets are stapled, then the productivity increases, but the thin paper cannot withstand transverse forces and tears, causing eyelet collapse

Engineering Contradiction:
Improvenumber of layers stapledVSAvoidpaper resistance to transverse forces
Core Design Contradiction:
ProductivityVSStrength

Solution Approach 1:

The staple support is maintained in position during the initial driving phase to prevent eyelet deformation, and is withdrawn only after the staple legs are largely bent over, ensuring the eyelet is already stabilized by the bent legs before the support is removed

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The timing of staple support withdrawal is changed based on the bending process progress - it is delayed until after the staple legs are largely bent over, which fundamentally changes the force distribution and prevents eyelet collapse in thin paper stacks

Inventive Principle:
Principle #35Parameter changes

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 solution minimizes deformation of the eyelet staples, even in products with few or thin layers, by ensuring the staple support is withdrawn after the bending process is complete, eliminating harmful forces that could cause the eyelet to collapse.

Implementation Method 1

the rearward movement of the staple support out of the area of the ring eyelet is effected by a cam or a cam which only becomes effective shortly before the bottom dead center of the stapling movement of the driver

Methodology Applied
Scientific EffectCam mechanism: Cam

Data Source

PatentEP1837197B1Stapling device with a stapling head for processing round eyelet staples
Publication Date: 2012.09.26 MULLER MARTINI HLDG
  • EP1837197B1 patent drawingFigure 1
  • EP1837197B1 patent drawingFigure 2
  • EP1837197B1 patent drawingFigure 3

AI summary

When stapling sheet-shaped materials with ring-eyelet staples (2), a staple support (6) with a support body (17) is provided in the stapling head (26), which supports the area of ​​the ring eyelet (3) during the driving process and is only moved out of the ring eyelet (3) when the legs of the staple (2) passing through the sheet-shaped material have been largely bent over.