Papers by Keyword: Parallel Grinding

Abstract: This paper deals with the roughness forming mechanics of aspheric surface, and based on the subsequent abrasive blade theory, which will form the final ground surface, the mathematical model of maximal valley height of ground surface during aspheric parallel grinding was established. Through simulation study, the influences of grain size, the speed of wheel and workpieces on the aspheric surface roughness were analyzed, and furthermore, through test, the proportional relation between the maximal valley height and the roughness was found.

Abstract: In order to ensure the machining precision of wedge nonaxisymmetric aspheric lens, a parallel grinding method is designed using a clamp with adjustable gradient. Based on the machining method, three path plans of machining are put forward. Simulation results show that the three methods have their particular advantages according to the different requirement of machining.

Abstract: In order to ensure the machining precision of wedge nonaxisymmetric aspheric lens, a parallel grinding method is designed using a clamp with adjustable gradient. Based on the machining method, three path plans of machining are put forward. Simulation results show that the three methods have their particular advantages according to the different requirement of machining

Abstract: The manufacturing system developed in this paper is mainly used for the ultra-precision grinding of the hard-cutting materials, such as high strength steel and carbonized tungsten, which are characteristics with axisymmetric aspheric surface. Under the priority of accuracy and grinding rigidity to design the key components of multi-axis linked parallel grinding system of aspheric surface, such as high speed grinding spindle, B axis grinding rotary table, clamps and center high adjusting system. Maximum speed of the grinding spindle is 90,000rpm, spindle rotating accuracy is 0.1μm, rotation-angle-accuracy of B axis is , center height adjusting accuracy is 0.1μm, using the system can realize parallel grinding of aspheric surface[1].

Abstract: Two grinding methods, parallel grinding and cross grinding, were applied to the horizontal-axis-type rotary surface grinding of silicon and tungsten carbide. It was found that the cross grinding method results in better ground surface roughness than parallel grinding for the silicon wafer and that an isotropic ground surface topography is achieved for both silicon and tungsten carbide by cross grinding.

Abstract: Parallel grinding is an effective method of aspheric moulds machining which is usually made of industrial ceramic such as silicon carbide (SiC) or tungsten carbide (WC), but if the spherical grinding wheel is not being with precision truing and dressing, the roughness and form accuracy of the ground aspheric surface should get worse, for this reason, in this paper, the influence factors of thoroughness and form accuracy induced by the wheel truing and dressing are studied firstly, and a new 3-axis CNC Ultra-precision grinding system which is based on the PMAC (Programmable Multi-axes Controller) is developed, through simultaneous motion of the controlled X, Z and B axis, the form errors which is induced by the grinding wheel can be improved theoretically, and the aspheric mould machining test shown that the surface roughness of Ra 0.025μm and the form accuracy of P-V 1.15μm are achieved.

Abstract: The roughness and profiles accuracy of aspheric surface are two key factors affecting the resolution and other characteristics of optical instruments. In this paper a new grinding system-parallel grinding system was built, and an CNC system controlled by PMAC (programmable multi-axis controller) was developed, the parallel grinding system can realize Arc Envelope Grinding Method (AEGM) only through controlling 2-axis and the wear of wheel was diminished, the tool path calculation was simplified. Using this system, the roughness and profile accuracy of aspheric surface are improved.

Abstract: It is a cost-effective technology to obtain aspheric optics made from optical glass and other brittle materials using pressing mould. The optical quality of molded optics is determined mostly by the surface quality of the mould, which means poor mould surface with lots of cutter marks will result in adhesion phenomena and error replication between the optics and mould. [1] In this article, a chatter model about parallel grinding system was presented, and the reasons of chatter induced by velocity feed back was analyzed and simulated. By using parallel grinding system integrated ELID technology, and wheel with greater cross-section radius in rough grinding and constant grinding velocity in fine grinding, the amplitude of cutter marks in the surface of mould was minimized and the quality of the mould surface was improved.