Coaxial linear motion and rotary motion converter

The invention discloses a coaxial linear motion and rotary motion converter. The coaxial linear motion and rotary motion converter comprises a housing, a rotary nut, a linear guide rod, a first bearing, a second bearing and an end cover, wherein the housing is of a hollow cylindrical structure; one end of the housing is provided with an opening, and is equipped with a first bearing flange; the other end of the housing is open, and is equipped with inner threads; the end cover is arranged at the open end of the housing; outer threads which are matched with the inner threads are arranged at theperiphery of the end cover; the inner side end of the end cover is equipped with a second bearing flange; the rotary nut is arranged in the housing, and one end of the nut extends out of the housing;a ring-shaped bump is arranged at the periphery of the rotary nut; the first bearing and the second bearing sleeve the rotary nut, and are separately positioned at the two sides of the ring-shaped bump; one end of the linear guide rod is connected with a linear moving end; the other end of the linear guide rod is equipped with threads; and the linear guide rod is connected with the rotary nut through threads. The coaxial linear motion and rotary motion converter can realize mutual conversion between linear motion and rotary motion which are coaxial, and has the characteristics of being compactin structure, small in size and wide in range of application.