Soft elastic foams: Rebound resilience with electronic measurement
In the past, the rebound resilience of materials was determined using a rebound pendulum in accordance with the requirements of the German Industrial Standard (DIN). However, some time ago, this standard was superceeded by DIN EN ISO 8307, which specifies testing using a ball dropped onto the specimen. The German company Zwick GmbH & Co. KG, Ulm, now offers a suitable device for testing according to this standard which automatically measures the rebound height and thus the rebound resilience using a light barrier. This avoids errors as easily occur when reading the results on manual testers.
The method is simple: a 16.3 g ball is dropped from a height of 500 mm onto the specimen. Depending on the elasticity of the foam, the ball will rebound to a certain height. This height is directly proportional to the rebound value and is expressed as a percentage. This device saves time due to its superior ease of use and short measurement cycles.
The strengths of the tester lie in the quality control of foam materials in production and in the inspection of incoming and outgoing goods. The compact device measures only 200x250x600 mm and has weight of only 11 kg.
A dual-line LCD is provided for display of the measured values and the median value in percent. Additionally, the tester comes with a serial RS 232C, V24 interface.