Abstract
In this paper, the torsional strength and the flexual rigidity of flexible shaft are measured, and then the effect of the constructed wire diameter and the number of coiled wire in the outer layer are obtained. As the results of the test, two types of faliure, that of breaking and that of buckling have been indicated. The breaking failure is caused basing on the strength of constructed wire and the number of wire.
The following are the results obtained;
(1) The torsional strength of flexible shaft depends on the wire of the outer layer.
(2) The breaking torsional moment Tmax are obtained as follows; Tmax=πdm2σBnm(D-dm)/8k in which dm the diameter of outer wire, nm the number of wire and k the experimental coefficient.
(3) The torsional buckling is produced in the case of long length of shaft.
(4) The critical torsional buckling moment Tcr is obtained as follows; Tcr=k1B/l in which B the flexual rigidity of shaft.
(5) In the case Tcr>Tmax, the flexible shaft is broken, and when Tcr<Tmax, the shaft is buckled.
