As models for biological molecular motors, Brownian motors have been studied recently by many workers, and their physical properties such as velocity, efficiency, and so on, have been investigated. They have also attracted much interest in an application to nanoscale technology. It is significant to study more complex systems, that is, coupled Brownian motors, in detail, since Brownian motors with a single particle have been mainly studied until now. In this paper, we consider Brownian motors coupled mutually with elastic springs, and investigate the dynamics of the model and the efficiency of energy conversion. In particular, we find that the center of the mass of the elastically coupled particles moves faster than the corresponding single-particle model, and also that the efficiency of the coupled-particle model is larger than that of the single-particle model.