Abstract: A tension gauge for measuring the principal tensions in an elastic material and providing specific information about the magnitude and direction of the principal tension. The tension gauge employs a frame structure over which an elastic material is stretched. A depressing device depresses the center of the elastic material a known distance and the force required for this activity is measured. In the device, either the contact surface of the depressing device or the frame structure is non-symmetric about two orthogonal axes. In either case, because of the non-symmetric nature, the relative sensitivity of the tension gauge to the major axis tension and minor axis tension in the elastic material will be different and fixed by the ratio of the major and minor axis of either the frame structure or the contact surface of the depressing device, whichever is non-symmetric. The principal tensions in elastic material and information about their magnitude and direction are determined.

Abstract: This invention is an electrostatic conductive fiber detector for use in detecting, counting and measuring the length of fibers down to O.1 mm and below with increased accuracy and reliability over prior art devices. It can be used for detection of fibers suspending in a flowing gas, in a nonflowing gas, or in a vacuum and its accumulated counts over a period of time is essentially unaffected by velocity of the fibers being detected.