Research On Flexible Fixture Design Of Automobile Instrument Panel

The automobile dashbord is a thin workpiece with curved surface.Because of its complicated shape and low rigidity,itfs easy to be deformed by force.So it must be processed with special fixture.However,automobile dashbords productions appear in small quantities,mudti-species characteristics.The traditional special fixture can only adapt to a automobile dashboard which raises production costs.In order to solve this problem,a flexible fixture which is able to adapt to a variety of automobile dashbords is studied and designed in this paper.Firstly,the geometric shapes and sizes of several common automobile dashbords were summarized by measuring and collecting.The models of the largest dashbord and the smallest dashbord were established and they were used for the following analysis.Three typical sections which were used to analyze the layout by the optimization module of ANSYS Workbench were extracted in the general model,and the optimum support scheme was obtained.Secondly,according to the layout scheme,the supporting part of the fixture was divided into front arc positioning module,below positioning module,flexible auxiliary positioning module and both sides positioning module.The structures of positioning and supporting units in each module were designed.Again,the changes of clamping forces in different processing positions were analyzed.The unreasonable structures of the equipment were proposed.In order to solve the problems,an independent clamping module was designed,and the flexible auxiliary clamping module was optimized.During the milling process,the switching process of the clamping units is tested.And a card fixture was designed and it was used to verify the feasibility of the support scheme by the application of this fixture in high pressure water cutting.Finally,in order to obtain the positions of the fixture supporting ends and the distance the ends moved when locating the workpiece,the event based simulation was put forward.The accuracy of data obtained by several common methods are compared.Through the second development of SolidWorks,the extracting and storing data of the points positions were realized.It provides basis for automatic positioning control of this flexible fixture.