Rock uniaxial tension and compression test device capable of realizing continuous conversion of tension and pressure

The invention relates to the field of rock mechanical property research, and particularly discloses a rock uniaxial tension and compression test device capable of realizing continuous conversion of tension and pressure. The device comprises an upper loading mechanism and a lower loading mechanism which are respectively connected with the upper end and the lower end of a rock test piece, and the upper loading mechanism and the lower loading mechanism have the same structure and are symmetrically arranged up and down relative to the center line of the rock test piece; the upper loading mechanism comprises a first bearing piece, a second bearing piece, a third bearing piece, a loading head, an upper spherical hinge, a lower spherical hinge and a hinge which are fixedly connected in sequence from bottom to top; the lower surface of the first bearing part is fixedly connected with the upper end surface of the rock test piece; and the lower end of the third bearing part is coaxially and fixedly connected with a sph