Portable device for measuring peripheral unevenness and diameter of wheel of railway vehicle

A portable device for measuring the peripheral unevenness and the diameter of a wheel of a railway vehicle is characterized in that one side of the upper surface of a magnetic base (1) is hinged to the lower end of a rotation arm (5), a rotation shaft at the upper end of the rotation arm (5) is matched with a small wheel (4), the rotation shaft is provided with a rotation encoder (15), the middle portion of the rotation arm (5) is connected with the middle of the upper surface of the magnetic base (1) through a tension spring (7), the other side of the upper surface of the magnetic base (1) is fixedly provided with a sensor support (13), the upper end of the sensor support (13) is connected with a displacement sensor fixing plate (9) which is connected with a displacement sensor (10) through threads, an optical trigger (11) is electrically connected with a data collector (2), and the data collector (2) is further electrically connected with the displacement sensor (10) and the rotation encoder (15). The porta