變速箱設(shè)計(jì)外文翻譯資料

1、The Engineering Meetings Board has approved this paper for publication. It has successfully completed SAEs peer review process under the supervision of the session organizer. This process requires a minimum of three (3 reviews by industry experts.All rights reserved. No part of this publication may

2、be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. ISSN 0148-7191Positions and opinions advanced in this paper are those of the author(s and not necessar

3、ily those of SAE. The author is solely responsible for the content of the paper.SAE Customer Service: Tel:877-606-7323 (inside USA and Canada Tel: 724-776-4970 (outside USA Fax: 724-776-0790Email: CustomerS ABSTRACTExperimental factors have great influence on the vibration medal test. U

4、sing a box body of automobile gearbox, firstly, the first several orders frequencies can be calculated by using finite element analysis method. Secondly, based on the vibration modal tests of box body of automobile gearbox, the corresponding modal parameters can be obtained on the both elastic suspe

5、nsion and elastic support; then the effect of the experimental results were discussed on different constraint conditions. Thirdly, by comparing the results of finite element analysis method with the experiment results on different constraint conditions, the reasons of the influence which caused by t

6、he constraint conditions were discussed. Finally, suggestion for reducing the errors induced by constraint conditions was put forward in the article. The results of the experimental Analysis have engineering significance.INTRODUCTIONAlong with the extensive application of dynamic signal analysis ins

7、truments according to quickly transformation (FFT, it become the mainstream that experiment modal analyze that frequency response test technique of transience excitation and random excitation with every kind identifying method of frequency domain time domain. These methods are widely used in the aer

8、onautics, astronautics, vehicle, warship, power, metallurgy, chemical engineering.etc. And it is getting the extensive application in the mechanical engineering realm. The extensive application of modal analysis technique turns to bring forward newly requirements on modal experiment with test techni

9、que. Its cores are increase the dependable with accuracy of experiment modal analyze. The experiment factors like constraint conditions in the test have got very big influence for experiment results. For advance toe modal analysis precision, the constraint conditions in testing must be considered. F

10、or the modal analyzing accuracy, the constraints conditions in the experiment are in processes of investigate by domestic and international expert's scholar 1-3. In this paper, mainly contribution is under the different stipulation to do vibration modal experiment of Gearbox, get the modal param

11、eters under the different stipulation, and then analyze the influence the results under the different stipulation deeply. By the contrast, the influence reason of constraint conditions to modal experiment results of Gearbox is detected. How to effectively reduce the analysis error aroused by constra

12、int conditions is investigate, and the different settle method are bring up.MODAL TESTS SYSTEM AND EXPERIMENT PARAMETER SETUPMODAL TEST SYSTEMModal test system includes to excitation system, signal picking up system, data collecting system and signal analyzing system 4.In the experiments, the accele

13、ration KD1005 is used to pick up vibration response signals. The excitation signal and respond signal are processed by DH5935N and2009-01-0773The Vibration Modal Tests and Analysis of Automobile Gearboxon Different Constraint ConditionsLi Shunming, Zuo Zemin and Qin JieNanjing University of Aeronaut

14、ics and AstronauticsCopyright © 2009 SAE Internationalthen is sent into the calculator. Make use of the DHDAS data collecting system to do FFT analysis of signals, to calculate transfer function. And make use of the DHMA modal analysis software to identify the modal parameters. The sketch map i

15、s as show in the Figure 1. ESTABLISHMENT OF THE EXPERIMENT PARAMETERS The modal parameters need to first set up before beginning the modal experimentation 5. The data collection is choice to make use of piezoelectricity accelerometer. The experiment method is to adopt the method that excitation in s

16、ingle point and collection response dates in many points. The parameter identification method is using multi-modal identifying method in frequency domain. Set the sampling frequency to 5.12 kHz, analysis frequency to 2 kHz 6. Fig 2 The solid model of gearboxFig 3 The grid chart of finite element mod

17、elFINITE ELEMENT ANALYSIS RESULT OF DYNAMIC CHARACTERISTIC ON GEARBOXThis paper using ANSYS software processes finite element modal analysis. This software is applicable to linear analysis. For nonlinear factors, for example, big strain unit, big distortion, or plasticity, they are neglected and not

18、 calculated.By finite element analysis of the ANSYS, the 16 ranks analysis results of gearbox are such as show in the table 1.The gearbox modal of finite element analysis is withdrawing 22 ranks. Removing 6 rigid modals, we get the 16 rank modal, and output the modal frequency of each rank. We can s

19、ee from above table 1, each rank of frequency that calculated by finite element analysis are distribute even, the high level frequency distribute are intensive comparatively.Because of the simplification of the theories model and the simulation error of constraint, above results may have the error c

20、ompare with real value. The reliability of analysis results consequently depend on experiment modal analysis for judgment.Table 1 Finite element analysis results of gearboxRanks 12 3 4 5 6 7 8Frequency(Hz332.48 482.05 550.02 621.25 662.30 780.23 905.82 980.05 Ranks 9 10 11 12 13 14 15 16 Frequency(H

21、z1079.50 1201.30 1268.96 1482.20 1559.82 1730.72 1838.45 1908.84ANALYSIS OF EXPERIMENT MODAL RESULTS ON GEARBOX UNDER THE DIFFERENT CONSTRAINT CONDITIONESTABLISHING OF SIMPLIFIED BOX MODELFirst, draw the gridding no the box surface. Then arrange the knot point on the gridding. Third according to wha

22、t knot order arranging, establish the simplified box model in the DHMAS modal analysis software. The simplification box model is such as show in figure 4. Fig 4 Simplified model of box and its modal griddingEXPERIMENT MODAL RESULT ANALYSIS OFGEARBOX The gearbox is propped by elastic support and elas

23、tic hang respectively. The way of elastic hang demand notice that the link point should be placed no or near to the modal knot as much as possibly. The modal experiment is caring through under above two kinds of circumstances respectively. The choices of sensor fixing position appropriately on the k

24、nots are 16, 35, 72, 82, and 106. And gearbox obtain the excitation by force hammer in every position ( knot 1 to knot point 112. Will import the test signal in to the dynamic signal analyze system DH5935N. After transform the excitation signal with response signal to frequency domain by FFT respect

25、ively, we obtain the frequency response function between the excitation points with response point. Based on superposition of all frequency response function, we can identify the modal parameters of gearbox. So for the experiment dates, it is needed to transmit into DHMAS modal analysis software, an

26、d get the modal parameters by analysis and computation. The modal frequency and modal damping ratio obtained by modal analysis are as table 2 shows. It can be seen that within the scope of certain frequency, the natural frequency number no the theories is more then the practice test result. This is

27、primarily for identifying main modal of gearbox in the examination, and setting the sensor to proper position, so some secondary modal are then ignored. Secondly some frequency might have been lost in real testing because of certain causation. The calculation of eigenvalue is to obtain all the frequ

28、ency within the analysis frequency band in the theories analysis. They include main modal and secondary modal. Moreover, because of the influence of larger rigid partly, at some natural frequency nearby, there are a lot of modal appear. Because of this phenomenon of frequency concentration, the natu

29、ral frequency number of the theories analysis sometimes will be more than that of examination. Furthermore, the simplification of the theories model and the simulation error of constraint condition will also result in windage of the calculation result compare with measure the results.Table 2 The com

30、pare of test results under the two structurerestriction methodsFiniteelement Experimental modal analysis hanging fixingElastic supportClassFrequency (Hz ClassFrequency (Hz Damp(%Class Frequency (Hz Damp (% 1 332.48 1 314.94 2.39 1 341.80 2.352 482.05 2 473.63 0.61 2 488.28 0.593 550.02 3 549.32 0.30

31、 3 556.64 0.544 621.25 4 625.00 0.85 5 662.30 5 661.62 1.27 4 668.95 1.26 780.23 6 786.13 1.05 5 771.48 1.127 905.82 7 864.26 0.67 6 898.44 0.738 980.05 9 1079.50 8 1076.60.29 7 1079.10 0.2310 1201.30 9 1184.08 1.18 11 1268.9612 1482.20 10 1477.05 0.62 8 1469.73 0.5913 1559.82 11 1574.71 0.64 9 1577

32、.15 0.4714 1730.72 12 1723.63 0.11 10 1718.75 0.2315 1838.45 13 1848.14 0.27 11 1850.59 0.29From the table 2, we can still see that the frequency values of elastic support fashion are greater than that of elastic hanging fashion. The elastic support fashion will result in additional vibration, and t

33、hen result in deviation phenomenon of frequency value, especially lowThe installing methods of structure may influence the measure results right, especially when the structure being installed on the support of more flexibility. Diagraph, the deviation is usually very big. Generally ithas 4 reasons a

34、s below: (a First modal (b Second modal (c Third modal (d 5th hanging fixing,4thelastic support(e 6th hanging fixing, (f 7th hanging fixing, 5th elastic support 6th elastic support(g 8th hanging fixing, (h 10th hanging fixing, 7th elastic support 8th elastic support(i 11th haunging fixing, (j 12th h

35、anging fixing,9th elastic support 10thelastic support(k 13th hanging fixing, 11th elastic support Fig 5 Part modals acquired from two fixing mode1. The outer Sid vibration is transferred into structure that is tested.2. The structure vibration is transferred into foundation and makes foundation beco

36、me a noise sources and then be interfered by these noise sources.3. The foundation connected or contacted with structure change the character of structure vibration and then result in measure error appear.4. Elastic packing have a slightly affection for lower frequency of structure but no affection

37、to middle and high frequency.When a structure vibration is tested, it is supported usually by elastic. If the stiffness of elastic support is large and the effect of vibration reduction is poor, the vibration measurement value of structure shall be strongly influenced. The additional vibration and a

38、dditional noise should be eliminated.For additional vibration that affected the measurement value of structure vibration, it is sometimes difficult to distinguish. This is because the additional vibration is usually mixed in the normal vibration of structure and sometimes can not affect the key char

39、acteristic of structure vibration. But the examination precision of structure is affected clearly by additional vibration. The methods below are advanced for eliminating the additional vibration:1. Make use of appropriate elastic support that has enough flexible character. The elastic support must h

40、ave enough compression amount and ensure is belong to elastic state. This will reduce the affect of additional vibration to examination precision of structure vibration.2. There are the ranges of the sensors position error and direction character. If it out of the ranges, the measure results of stru

41、cture vibration will be inaccurate. Sometimes the result is false.3. When the structure need to rigid fixing, it must be avoided that the resonance appears on one medium frequency or high frequency. Otherwise this will influence the measure precision.Part modal figures acquired from two fixing mode

42、are shown as fig 5. In each sub fig, the left fig is the modal obtained by hanging fixing, and the right fig is the modal obtained by elastic support. Due to the frequency loses in the measure results of hanging fixing, the 4th and 9th modal dose not appear compare with elastic support. Analyzing ab

43、ove modals, it can be seen that the structures modals can be described as two kinds approximately. First kind is main modal. On this modal, the vibration character is come from whole structure. The second kind modal is local modal. The vibration character is only come from part of the structure in t

44、his condition.In the fig 5, fig.(a is local modal, represent the contraction and extension. The fig.(b is holistic modal, and represents the torsional vibration of gear box circling Z axial. The fig.(c is holistic modal, and represents the torsional vibration of gear box circling X axial. The fig.(d

45、 is holistic modal, and represents the banding vibration of gear box circling X axial and the local vibration of foreside gear box. The modal character of other fig can also be analyzed clearly.CONCLUSIONThe different constrained conditions of modal test that affect gear box vibration are analyzed.

46、The vibration modal analysis results of gear box on two constrained conditions show the difference. Four affected causation for modal analysis results are advanced via compare. The eliminated methods of additional vibration are analyzed. It can be seen by comparison of two tests condition that the i

47、nfluences are clear. After four class modal, the frequency loses appear and the modal shape disaccord is clear. It can also be seen from modal test that the structures modals can be described as two kinds. At different test condition, the modal kind may be different.Compare the analysis results of finite element computation with modal test, the conclusion are reasonable and can be as a referen