专利名称：Apparatus for the measurement of internal
friction of materials
发明人：CHEETHAM IVAN CLIFFORD申请号：US51193865申请日：19651206公开号：US3400571A公开日：19680910
摘要：1,121,310. Measuring internal friction electrically. DUNLOP CO. Ltd. Dec. 1, 1965[Dec. 10, 1964], No. 50244/64. Heading G1N An annular specimen 24, Fig. 1 of a materialof which the internal friction is to be measured, is attached to a plate 23 fixed to a shaft21 which is constrained to rotate against the resisting torque of a coil spring 40, by aplurality of balls 15 sandwiched between the specimen and a further annular member 14,which is rotated at a constant speed by an electric motor. The angular displacement ofthe plate 23 is measured by a fixed pointer 39 and a graduated disc 38 attached to theshaft 21; or else by a potentiometer 47 having a moving tap 45 connected to the shaft 21,this displacement representing the internal friction. The contact 45 is normally out ofengagement with the potentiometer track 47 and is biased into engagement bysolenoids 51 which act via a member 48 to depress the potentiometer arm and producean output signal at regular intervals thus enabling a series of points on a chart to beplotted. Values of internal friction are plotted during a continuous change in
temperature of the specimen produced by filling a reservoir 25 attached to the specimencarrying plate 23, with liquid nitrogen and allowing this to evaporate. Elevatedtemperatures are achieved by a heating coil 32, or by blowing hot air into the glass
chamber 36 enclosing the plates. The temperature of the specimen is measured with athermocouple 34. A paddle wheel 42 in an annular oil bath 43 damps the rotationalmovements of the shaft, 21; and a weight 52 at the bottom of the shaft 21, which ismounted in needle point bearings 26, 53, provides the required axial force between thesample plate 23 and the driver plate 14.
申请人：DUNLOP RUBBER COMPANY LIMITED
更多信息请下载全文后查看
因篇幅问题不能全部显示，请点此查看更多更全内容