Cam Throat Mechanism for Paper Shredder Jam Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Shredders often jam when too many sheets of paper are fed into the feed throat, leading to user frustration and mechanical strain.
Innovation Solution
A shredder mechanism featuring a thickness detector and a blocking mechanism that prevents further insertion when articles exceed a predetermined thickness threshold, using a cam mechanism to engage or disengage articles based on their thickness, thereby preventing jamming.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the feed throat is left open without restriction, then users can easily insert articles for shredding, but the shredder jams when too many sheets are fed in
Solution Approach 1:
The cam mechanism is positioned to engage with articles before they fully enter the shredder throat. When an article exceeds the maximum thickness threshold, the cam mechanism proactively engages to block further insertion, preventing the jamming condition from occurring in the first place rather than reacting after the jam occurs
Solution Approach 2:
The cam mechanism acts as an intermediary blocking element between the user's insertion action and the shredder's cutting mechanism. This intermediate component detects excessive thickness and physically prevents over-insertion, mediating between the need for easy access and the need to prevent jamming
2Reliability
If a blocking mechanism is added to prevent over-insertion, then shredder jamming is prevented, but the device complexity increases
Solution Approach 1:
The cam mechanism is designed to be self-actuating through the geometry of the cam surface and spring bias. When an article of excessive thickness is inserted, the cam mechanism automatically engages the blocking position without requiring external sensors, motors, or control systems. The mechanism serves itself by using the physical dimensions of the article to trigger the blocking action
Solution Approach 2:
The cam mechanism uses simple, inexpensive mechanical components including a cam surface, spring, and blocking member. These basic mechanical elements are far simpler and cheaper than electronic sensors, microprocessors, or automated control systems that could achieve the same jamming prevention function
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
Prevents shredder jamming by limiting the number of sheets that can be inserted, reducing mechanical strain and ensuring efficient operation.
Implementation Method 1
the cam mechanism is biased to a disengaged position and movable to an engaged position responsive to insertion into the throat of the at least one article above a predetermined maximum thickness threshold
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A shredder includes a housing having a throat for receiving articles be shredded and a shredder mechanism. The shredder mechanism includes a motor and cutter elements, and enables the articles to be shredded to be fed into the cutter elements. The motor drives the cutter elements to shred the articles. A cam mechanism is provided in the throat and is movable from a disengaged position to an engaged position responsive to insertion into the throat of articles above a predetermined maximum thickness threshold. In the engaged position, the cam mechanism engages the articles to prevent further insertion thereof into the throat, and in the disengaged position the cam mechanism is disengaged from the articles to permit further insertion thereof into the throat. The cam mechanism may be movable between a closed position and an open position. In the closed position, the cam mechanism is configured to block the throat.