Device for measuring rotational inertia and friction moment of ball screw

The invention relates to a device for measuring rotational inertia and friction moment of a ball screw. The device comprises a bottom plate, two linear guide rails, the ball screw, a torque sensor, a servo motor, a mobile platform and two friction moment measuring mechanisms. Each linear guide rail is provided with two sliding blocks. The two ends of the ball screw are supported by the part, located between the two linear guide rails, of the bottom plate in a rotary mode through a fixed supporting base and a floating supporting base. One end of the torque sensor is connected with the end, supported by the fixed supporting seat, of the ball screw through a coupler. An output shaft of the servo motor is connected with the torque sensor through a coupler. The two friction moment measuring mechanisms are arranged on the two sides of a screw nut base respectively. Each friction moment measuring mechanism comprises a cantilever. A connecting sleeve is arranged at the tail end of each cantilever. Each connecting sleeve is connected with a sliding bar through a vertical linear bearing. The other end of each sliding bar is connected with a pressure sensor. Each sliding bar is sleeved with a spring. The bottom of each pressure sensor is connected with a universal ball. The bottom of each universal ball makes contact with a linear slab which is parallel to the ball screw. The linear slabs are tightly connected to the bottom plate.