Forced Vibrations of the System with Two Degrees of Freedom with Coulomb Damping

抄録

In this paper, we analysed the motion effected by harmonic disturbing displacement of the system which has two masses suspended by two springs and a constant friction between masses or between the mass and the supporting ceiling, and obtained an analytical solution in the domain of vibrations with or without stops. Some experiments were carried out, showing close agreements with the theoretical analysis. By these studies, the following results were obtained : (1) In the resonance, when the friction is smaller than a certain definite value, the amplitudes of masses become infinitely large, and the friction which is larger than this value causes a motion with stops or a motion without the relative displacement of masses. (2) At 1/3, 1/5, 1/7, …… of natural frequencies, any smallest friction causes a motion with stops. (3) At infinitely high frequency, in the case that the friction between two masses is larger than a certain definite value, a motion with stops or a motion without relative displacement will occur, and in the case that the friction exists between the mass and the supporting ceiling, any friction does not cause a stop motion.