In many production processes, it is necessary to detect perforations and leaks in injection-moulded products, films or other products like gloves and delicate material for applications in the medical industry and for medical use. Existing methods such as vacuum, pressure or optical control are often not applicable to transparent products or shapes that are difficult to handle. High voltage sparks can be used in a controlled way to detect perforations in these cases. A spark from a special electrode to a ground reference can be detected by the high-voltage generator and counted or relayed to other connected electronics and evaluated. The detection is non-contact so that there is no contamination of the material during hole-detection. High voltage electrostatic perforation detectors like the small footprint, Perfomaster and the CM 5 high-voltage generator provide the hardware and the software to generate a controlled spark, detect this spark and convert the spark to a pulsed signal for use in other equipment.
The Perfomaster provides the hardware and software to generate a controlled spark over, detect this and evaluate the spark over to produce a pulse signal. The pulse signal is available on the output connector and can be used for counting the detected spark-overs and thus perforations.
In order to detect perforations in a moving material web, this special electrode is equipped with a resistance per emitter. When a perforation passes the electrode, there will occur a controlled spark over.
CM5 is fully backwards compatible with ECM30/60 and ECM DI30/60.
For basic users a quick set-up menu is provided to set-up the generator to function as an ECM30/60. The Menu is available in English, German, French and Italian.
The pulse signal is available on the output connector and can be used for hole detection or counting the detected spark-overs for perforations detection.Perforations in plastic webs and products can be detected and counted. Perforations in moving webs can be detected with a special detection bar and a high voltage generator. Perforations will be detected but not localised. A perforation in the film will create a spark through the material and will generate an output signal on the charging generator. Due to the strong electrical field placement of anti-static bars after the perforation detection is mandatory. Perforations in products can be detected using high voltage to create a spark through the perforation. Common application is testing the injection point of injection moulded products e.g. yoghurt cups, bottles and containers.
Perforations in a web material can be used to determine the position of the material in the machine. The perforation can be the “tear-off perforations” of bags or a deliberate perforation made to determine a position. Perforation detection with the use of high voltage is not depending on the material surface and can also be used with transparent materials. When a perforation passes between the high voltage electrode and a ground electrode, a spark is generated. This spark will be detected and a pulse signal will be available for use by the machine control system.