CNC grinding machine fixture design improvements

2018 - CNC grinding machine fixture design improvement 12 - 14 jian-xia sun ( Avic taiyuan aviation instrument co. , LTD. ) Abstract: the fixture is one of the important craft equipment in the product manufacturing, its quality, efficiency and reliability of the product processing quality and production efficiency plays a decisive role. Through the introduction of the concept of nc grinding machine and fixture, expounds the content of the fixture design, comprehensive analysis from the location to the error analysis, to ensure the machining accuracy of the content, so as to provide reference for future related work. Key words: fixture assembly; Bolt; Clamping force. Machining precision in machining process, machining process system is composed of machine tool fixture, machine tool, cutting tool and workpiece. Fixture design for process system is not only the different content, want to consider, machine tool cutter interference in the specifications ( Such as the radius of gyration table, stroke limit) Wait for a problem. Application of import, the highly effective numerical control equipment, in improving the level of machine tool fixture design at the same time, also changed the machining high precision fixture manufacturing capability. Only fully considered the scene equipment conditions of use, can by changing the fixture scheme, such as improve the efficiency of fixture design and manufacture of processing method. The most simple and efficient method is the best way. My company imports a nc face internal control composite cylindrical grinding machine using fixture domestic cannot make, can only entrust the original fixture manufacturers, therefore, the company has been using the included two fixture processing two kinds of products, equipment utilization rate is low. In order to reduce the jig cost, improve the utilization rate of machine tools, jig localization design has very realistic significance. 1 problem analysis based on the analysis of the numerical control end the working principle of the internal control of cylindrical composite grinding machine included fixture in common with other internal grinder is clamp concrete are elastic diaphragm, the difference is the workpiece clamping device. With imported machine tools machining, the spindle speed is high, after processing the workpiece end face, can produce a pull forward to artifacts. In the design of clamping device, adopts the form of the whole welding, and install the clamping claws with card design for the present body hole, jaw head in the form of triangular wedge. 2 fixture design difficulties of the fixture design is difficult, it is the overall welding structure, existing conditions will not be able to process the manufacturing; Difficult to determine the jaw ( 3) Head triangular wedge Angle, and in the process is difficult to ensure that its consistency and symmetry. 3 new designs in the mould design, it is difficult to control the size of the process and precision, often rely on during assembly adjustment method to get the corresponding precision. In view of this, to the disintegration of fixture design, the bolting assembly, through the adjustment method to obtain the required accuracy. In the collapse of the design, need to pay attention to the following: (1) when designing parts, shall establish the necessary benchmark as the entire assembly adjustment datum; Teeth can't be divided exactly by 3 (2) for workpiece artifacts, considering import machine speed is higher, should choose the size and tolerance of each parts, avoid fixture function imbalance and appear in the process of using the marks or workpieces is unqualified; (3) in order to enlarge the using range of jig, consideration should be given certain adjustment range, in order to meet the needs of different size workpieces, avoid unnecessary repetition of design; (4) because the common grinding machine is difficult to assure card claws triangular wedge head of machining accuracy and consistency, therefore, should make full use of imported CNC tool grinding machine. Through the analysis of the design thought of the fixture, combined with the production conditions of the field of machine tool fixture design. In the design of fixture, want to consider the following: (1) together with the present situation of production and process, analyses and studies the technological process, puts forward the problems need to be solved in fixture design. (2) familiar with fixture of the specifications of the machine tool, performance parameters and the processing principle, avoid design of fixture and machine tool does not match. Familiar with the content, sometimes to deal with the problems in the fixture design has a lot of help. (3) for fixture on some of the key parts and components, with the general processing equipment is unable to ensure the machining accuracy. Through understanding of the existing equipment, can be a preliminary analysis of the feasibility of the designed fixture processing and manufacturing, improve the success rate of design. (4) with the method of the system, innovative ideas to solve the problems in the design. The fixture is made up of machine tool, cutting tool and workpiece to form part of the process system. In the design of fixture, from the Angle of the system to consider and solve problems, using the experience of similar fixture design, constant innovation. (5) through the adjustment of the fixture design and using the methods of analysis, in the design, want to consider the accuracy of workpiece, adjust the benchmark and space, consider using a fixture in security and complexity. 4 conclusion a good set of fixture must ensure the workpiece processing quality, reduce the labor intensity of workers, improve labor productivity, and fixture structure is simple, operation is convenient, safe, easy to manufacture and maintenance, at the same time, also can reduce the manufacturing cost. Design a good fixture must be based on the present, based on the study of the site, is now fully. Source: 'science and technology and innovation' 20, 2015