Springs 4 and 5, acting through intermediate link 8 on two-arm lever 3, develop a bending moment on the portion of test-piece 2. Upon rotation of shaft 1, test-piece 2 is subjected to the simultaneous action of bending and torsion. Spring 5 is precompressed and adjusted to exert a definite force. It is secured at one end to a fixed base and at the other to component a which belongs to rod b that slides in hole c of the base. Spring 4 is secured at one end to the fixed base and at the other to two-arm lever 7 which turns about fixed axis A.
$817$LW,M$