Cutting Unit With Pneumatic Suction For Strap Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cutting units for removing straps from the bottom wall of 'book-pack' cigarette packs often fail to ensure complete removal of the strap after cutting, leading to issues like strap loss in the machine or random wrapping positions, which affect the quality of the final product.
Innovation Solution
A cutting unit equipped with two coaxial and horizontally arranged rotary blades, accompanied by a pneumatic device that applies suction and a jet of air to ensure the strap is properly cut and removed from the bottom wall, and a sucking duct to collect the strap.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If suction is applied to capture and remove the strap after cutting, then the strap should be removed from the bottom wall, but the strap remains stuck in the bottom wall and is not removed
Solution Approach 1:
The cutting operation is divided into two distinct phases: cutting phase where blades sever the strap, and removal phase where the strap is detached and extracted. This segmentation allows optimization of each phase independently, ensuring reliable strap removal through sequential blade retraction and suction activation.
Solution Approach 2:
The blades retract into their housing before the suction mechanism activates. This preliminary action creates the necessary condition for effective suction by removing the physical barrier that prevents strap extraction, thereby ensuring reliable strap removal without increasing overall system complexity.
2Manufacturing precision
If the strap is not completely removed, then the cutting operation is incomplete, but the strap may be lost in the machine or wrapped in random positions affecting quality
Solution Approach 1:
The system incorporates a sensor that detects the presence of the strap after cutting. This feedback mechanism triggers the blade retraction and suction activation sequence only when needed, ensuring complete strap removal while maintaining packaging throughput by avoiding unnecessary operations.
Solution Approach 2:
A suction mechanism is employed to reliably capture and remove the cut strap from the bottom wall. This pneumatic approach ensures complete strap removal without requiring complex mechanical extraction systems, thereby maintaining manufacturing precision while preserving packaging productivity.
3Ease of manufacture
If two parallel and adjacent rotary blades are used to make the cut, then the strap can be separated from the bottom wall, but the strap remains stuck and is not removed by suction
Solution Approach 1:
The blade assembly is designed to dynamically retract into its housing after cutting. This dynamic movement transforms the static cutting structure into an adaptive system that facilitates strap removal, maintaining ease of manufacture while significantly improving strap removal reliability through the retraction-suction sequence.
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 effectively ensures the complete removal of the strap after cutting, preventing strap loss and ensuring consistent packaging quality by maintaining the strap in the correct position during the wrapping process.
Implementation Method 1
a pneumatic device that applies suction and a jet of air to ensure the strap is properly cut and removed from the bottom wall
Implementation Method 2
a pneumatic device that applies suction and a jet of air to ensure the strap is properly cut and removed from the bottom wall
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A cutting unit (8) and method to remove a strap (B) from a wall (6) of a pack (1), in particular of smoking articles, which is fed along a path (P). Two rotary coaxial blades (10) are provided which are mounted so as to rotate around a same rotation axis (11) at a given distance from one another and make a double cut (7) in the wall (6) of the pack (1) which separates the strap (B) from the rest of the wall (6) of the pack (1). A pneumatic device (16) is also provided configured to apply, between the two rotary blades (10), suction, which acts upon the strap (B) during the execution of the double cut (7).