Based On The Non-contact Ball Nuts Raceway Grinding Automatic Knife Technology Research

Compared to the contact-mode positioning of grinding wheels to the external thread, it’s harder to study the method and design the system of automatic non-contact positioning to the internal thread, because screw nuts’structure size is small and the inner space is limited. In order to meet the technological requirement of positioning to the internal thread during the finish grinding process, the thesis does research on the automatic non-contact positioning technology for grinding wheels to the internal thread of ball nuts.According to the positioning requirement and characteristic of grinding wheels, the principle of automatic non-contact positioning to the internal thread has been studied. In this chapter, the following tasks have been done:design the positioning system, state the general working steps, put forward several positioning methods (Single-switch mode, multi-switches mode, improved), and compare these methods qualitatively at the sides of efficiency, accuracy, etc. The compensation of positioning error has also been analysed.Based on the principle of non-contact positioning to the internal thread, the principle test-bed has been designed, and the experiments have been done through it. In this chapter, the following tasks have been done:design and assemble the test-bed, connect the circuit, develop the experimental software by Visual Basic to control the motion of test-bed and acquire the data. Acquiring from the experiments aimed at several elements (sensing distance, positioning velocity, angle, thread pitch, etc.), a mass of data has been analysed and processed reasonably to prove the feasibility from the fundamental point.After the fundamental experiments, the field test is done through the female thread machining tool. In this chapter, the working steps are improved upon the automatic positioning module from the point of safety and the practical view. Acquiring from the field test aimed at several elements (positioning velocity, angle, thread pitch, etc.), a mass of data has been analysed and processed effectively to prove the feasibility from the practical point.The whole technical study contains the design of principle and methods, the fundamental experiments, the field test. The feasibility and veracity of this technology that the inductance approach switches could be used to the automatic non-contact positioning to the internal thread of ball nuts are successfully proved.