ELONGATION GUAGE

PURPOSE:To enable simple and accurate measuring of elongation of a test piece until it is shorn, by a method wherein contacting probes are individually attached to the upper and the lower marked point of the test piece, the contacts are brought into press contact with a resistance strand, and a change in electric resistance between the contacts is utilized. CONSTITUTION:Two contacting probes transmitting a displacement of the test piece are attached to an upper and a lower marked point, and a contact is insulated and secured to each contacting probe. The contacts are then caused to make contact with a resistance stand under a given pressure, and a displacement caused due to a loading of the test piece is converted into the changing rate of the electric resistance of said resistance strand to perform a measuring operation. An upper contacting probe 2 and a lower contacting probe 3 are attached to each marked point of the test piece 1, and contacts 5 and 6, secured to the contacting probes via an insu- lating substance 4, are pressed against a resistance strand 8 being placed on an insulating plate 7, by use of a spring 10. The elongation of the piece under test is determined in the value of the change in the resistance of the resistance strand, and can be easily and accurately measured until the test piece is shorn.