| 摘要 |
A torsional oscillation device for testing plastics materials having a first clamp for gripping one end of a plastics material sample in a tempering chamber, and a second clamp for gripping the other end of the sample and rigidly connected to an oscillation body. The oscillation body, second clamp and the sample form a torsion pendulum in which oscillations are produced by a means through the oscillation body and a light transducer through a window in the oscillation body produces an electrical signal whose magnitude is dependent on the position of the oscillation body. The output of the transducer is connected to the actual-value input of a variable gain amplifier in a control device that drives a servo-motor which pivots the first clamp about the torsion pendulum axis. The nominal-value input of the control device corresponds to a predetermined relative position of the oscillation body and the part of the transducer not taking part in the pendulum oscillations.
|
