Parametric Analysis And Kinetics Research On Lifesaving Descending Device

A lifesaving descending device is for emergent escape from a high building, and it is widely used in hotel,apartment,hospital,house and so on. It can be used as building rescue device when emergency happens and used as high altitude working device usually.Descending device is a kind of new product which is developed in these years, and there hasn't been an integrated design system. A lot of deficiencies come forth in practice, for instance, short service life,occurrence of great impact when people falling to the ground,complicated structure,large volume,inconvenient operation,high price and so on. Descending device which is a product of Jilin Hengan Electron Machinery Co.Ltd is redesigned,optimized and analysed. On the condition of satisfying the material strength, the volum,the developing cycle and the cost are reduced. A better one which named JSH-100/35-30 is achieved and the deficiencies are improved. The following contents are studied in this thesis.(1) Theoretically, descending device's structure is redesigned and improved,technical parameters are determined based on the original design parameters and theoretically analyzes the improved gears whether satisfy the intensity requests. Theoretical calculation results will be used to examining the results of simulation and lay the foundation for the following analysis.(2) For the sake of making the course of design automatic and shorting the develop cycle, in this thesis, a descending device's CAD system which comprises 3D parametric modeling and optimum design function is built based on UG/Open API,UG/Open MenuScript,UG/Open UIStyler,VC++, etc. Descending device's 3D parametric modeling and optimum design are accomplished with the system, and satisfying results that the volume is 0.897 times the size of JSH-100/35-30 descending device,reducing the cost,shortening the develop cycle are achieved. Through comparing the results of program with results which are achieved from MATLAB's optimization box, proved that the program is available. The CAD system can be used in descending device's design and have great practical value.(3) A virtual prototype is built using UG/Motion module based on the results of the optimization above. Through dynamics simulation analysis, component's contact dynamic and kinematic characteristics are accurately displayed while the virtual prototype working and computer simulating of the gear dynamic contact force is realized. The speed of rope wheel is 0 .89m/sand the transmission ratio error is 3.16% which is smaller than 4% , from which we can find that the optimized structure satisfies the design requests. Through experimental analysis, we can find that the experimental results are consistent with the simulation results which will provide the reliable reference data for the product research.(4) The finite element analysis of principal axis that is the supporting component and the planetary gear sets are performed using UG/Structure module, and the biggest stress of principal axis and the biggest tooth root bending stress,contact stress of tooth surface are achieved. From analysis and the comparison of theoretical calculation and simulation results, we can find that the product which is optimized based on the original satisfies the material intensity requests and the manufacture implementation feasibility is guaranteed.Research fruits and methods in this thesis have important theory and project reference value. Using the virtual prototype to replace the physical prototype, we can not only confirm the design feasibility in real time, simulate its future active status and movement behavior and discover the design errors in time, confirm the reliability of its function and performance, make the design process automatic, avoid the expensive and time consuming physical experiment, but also have the product met the design requests and the manufacture implementation feasibility is guaranteed. There will be great practical significance to reducing the manufacturing times of physical prototype,product development cycle,research and development cost, enhancing the production efficiency and product quality.