Die cutting spring ejection method
Publication Date: 2005-Apr-04
The IP.com Prior Art Database
AbstractA mechanical spring piston is disclosed. This has been designed to eject unwanted material during die cutting of corrugated board and other die-cut material. It consists of a spring loaded piston inside a cylinder.
4 April 2005
Subject Die cutting spring ejection method
A mechanical spring piston is disclosed. This has been designed to eject unwanted material during die cutting of corrugated board and other die-cut material. It consists of a spring loaded piston inside a cylinder.
A critical part of the corrugated board die cutting process is the ejection of unwanted material. This material often adheres to either the cutting blades or the cutting blank due for various reasons. Solutions up to now have included the use of elastic type materials such as rubber / elastomer / neoprene / diaprene etc, which are compressed during the die cutting process, and upon the release of compression expand and push the unwanted material out. However elastic materials may not produce sufficient ejection forces with some corrugated blanks.
Rota Die International Pty Ltd, part of Amcor Ltd and based in Melbourne, Australia, have developed a mechanical ejection device. The device they are using (an 'ejection piston') consists of a steel piston inside of steel cylinder of the following approximate dimensions:
* Uncompressed length - 46 mm
* Compressed length - 31 mm
* Diameter of piston - 12 mm
* Diameter of cylinder - 17 mm.
Obviously other dimensions will produce a similar effect. The attached photographs show the pistons when mounted on a rotary cutting die.
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