Ball Screw Friction Torque Measuring Instrument Developed And Its Experimental Analysis

Precision ball screw unit is the key part of NC machine, and its manufacturing level determines the precision level of NC machine to great extent. With the development of NC machine oriented to high-speed, high-precision, multi-purpose and environmentalization, the performance of ball screw unit is demanded higher.The friction moment is an important usage function parameter of the ball screw unit, whose variation has effect on dynamic characteristic of ball screw unit. Therefore it is a basic request for the factory examination to measure the friction moment of ball screw unit. At present, operators usually estimate the ranges of friction moment values by "hand feeling" in most factories. The existing measure instruments have many deficiencies in function and precision. According to this, we develop the measure instrument for friction moment of ball screw unit.This new developed measure instrument includes two parts, superordinate computer and subordinate computer. The subordinate computer adopts MCU to realize many functions, such as "Real-time displaying the friction moment datas and the curves", "Printing the measure reports", "Communicating with superordinate computer". The superordinate computer can "Process the data defers to the national standard request", "Preserve datas", "Print the measure reports" and "Manage files". The subordinate computer can be used separately from the superordinate computer. This measure instrument can be operated easily and run stably.This article commences from appearance mechanism of ball screw friction moment, combining its structure characteristics, analyzing influence factor of ball screw friction moment and modeling. Then the hardware, software and anti-jamming design is exhaustively expressed. Finally, the frequency spectrum of the experiment data is analyzed, which further verify the results of theoretical analysis.