DEVICE FOR REPRODUCIBLE MEASUREMENTS OF ROLL HARDNESS
Original Publication Date: 1980-Oct-31
Included in the Prior Art Database: 2004-Apr-02
Xerox Disclosure Journal
It is known to measure the hardness of rubber compositions by using a Shore A durometer gauge. Typically, a Shore A durometer is slidably mounted on a vertical stand with a horizontal platform attached to the lower end of the vertical stand. The Shore A durometer is generally a meter having a needle point extending downwardly from the bottom of the durometer. In measuring the hardness of a rubber sample, the sample is generally provided in the form of a pad or sheet placed on the horizontal platform. The Shore A durometer is then dropped from a predetermined height from the sample on the vertical stand. The depth of indentation of the needle point into the sample is a measure of the hardness of the sample. The difficulty in using such a device to measure the hardness of a roll covered by a rubber composition is that it is extremely difficult to obtain reproducible measurements. It is difficult to have the needle point of the Shore A durometer land on the same point on the circumference of rolls when the rolls are placed on the horizontal platform.