外文翻譯原文.pdf

內(nèi)蒙古工業(yè)大學(xué)學(xué)報(bào)JOURNAL OF INNER MONGOLIA第 22 卷第 2 期 POL YT ECHNIC UNIVERSIT Y Vol. 22 No. 2 2003 c I | : 1001- 5167( 2003) 02-0153-04Inner M ongolia Polytechnic UniversityDepartm ent of M echanical EngineeringT he 11th Sino-Polish Conference on CAD in M achineryHuhhot, China, Oct ober 2002ZHANGYeCollege of Mechanical Engineering, Inner M ongolia Polytechnic University, Huhhot, 010062T HREE-DIM ENSIONAL ENT IT Y M ODEL AND M OVEM ENTEM ULAT ION OF REDUCER BASED ON U G PL ANEAbstract: This article introduces to m odeling for reducer w ith three-dimensional entity by M OSWLING module in the latest edition U GN X of UG softw are, w hich mainly concern w ith model of the maincom ponents such as shaft, gear, gear shaft, mount and cover andcom plete cor responding assembly. Then, car ry out movement emula-tion for all the assem bly w ith M OT ION module.Keywords: UG; three-dim ensional entity model; reducer; emulationU G is three-dimensional entity model plane which integrates CAD/ CAM / CAE, and is computeraided design, analysis and manufacture softw are w hich is used w idely in the w orld. There are severalpr oblem s should be paid attention to in this article: involutes tooth profile m odel of gear teeth, hol-low ing operation of cover w hen modeling, location betw een gear shaft and gear when assem bling.1Plottinginvolutestooth profileof gearteethInvolutes tooth profile of gear teeth can be plotted with expression in UGq3r. On the otherhand, this ar ticle pr ogram for involutes tooth pr ofile of gear teeth w ith V C+ + 6. 0 and save coordi-nate value of tooth pr ofile surface in corr esponding data file, and plot involutes tooth profile of gearteeth using read point fr om file in spline w ith the defined point.Polar coordinates parameter equation of involutes isq4rr k = r bcosnullknullk = invnullk = tgnullk - nullkmake rk and nullk go to x k= r kccosnullkyk = rkcsinnullkand spr ead w ith trigonom etric expressions, can get:xk = rbcqcos( nullk+ nullk) + (nullk + nullk) csin(nullk+ nullk )ryk= rbcqsin(nullk+ nullk) - (nullk+ nullk )ccos(nullk + nullk) rHere rk is radius of involutes tooth profile at K point, nullk is angle of involutes at AK segm ent, r b is baseradius and nullk is pressure angle at K point.Fig. 1 Fig. 2Program w ith VC+ + 6. 0 and change (nullk + nullk ) fr om 0 to 180, can get corresponding xk and yk,and save them in corresponding data file jkx. dat. The results like Fig. 1.Inser tCurveSpline in UG main menu , click Through Points button after show ing dia-logue, then the system show dialogue Spline Through Points like Fig. 2. Click Points From Filebutton and select before-mentioned data file jkx. dat, can get corresponding involutes like Fig. 3.Fig. 3154 = v 2003 MBecause tooth thickness and tooth spacew idth of reference cir cle is equality, the opposite centerangle of gear teeth and tooth space is equality, then the opposite center angle of half tooth thickness is12c3602z , viz90z , here z is number of teeth. XC axis should be rotated nullk+90z and m ake the above nullkexpression go to, cor ner is tgnullk- nullk + 90z . Because of the pressure angle of r efer ence circle of standar dgear is 20, so XC axis should be rotated ( tg20- 203. 1415926/ 180) 3. 1415926180+ 90z . Plot aline at XC axis, and select the line as center of m irror and m ir ror involutes w ith Existing Line in M ir ror Through a Line. T he r adius of the angle betw een tooth profile surface and roof is =c* cm1- sinnulli, here m is module, nulli is nominal pressure angle, c* is bottom clear ance coefficientq2r. At last,can get three-dimensional entity model of gear w ith tr ipping, cornering and str etching. like Fig. 4.Fig. 4At the sam e method, can get gear teeth involutes tooth profile of gear shaft.2Someproblemsshouldbepaidattentiontowhen modelingcoverHollow cover after completing the whole model of cover , can get partial entity and cant get theperfect full entity. Here, we use Region in Hollow and change cover into tw o par ts: bearing seat,pr otuberant level and boarding body w hich is connect w ith mount is one par t, the other is anotherpart, and hollow separately. The key point is the two parts cannot Unite before hollow ing and mustbe United after hollow ing. We think the complicated body should be disintegrated into simple bodiesand be hollowed separ ately, then U nite.155 2 ZHANG YeThree-Dimensional Entity M odel and M ovement Emulat ionll3Locationof gearshaftand gearwhenassemblingAxial location between gear and gear shaft is not confir med w hen they are assembled on mount,so intervening can happen among gear teeth. T here are eight types r estriction in UGq1r, such as Mate,Align, Angle, Parallel, Perpendicular, Center, Distance and T angent, but they all cannot set upmating relation of tw o gears. T herefore, it is necessar y to plot corresponding location surface duringthe course of entity m odel of gear shaft and gears. Here w e plot centerline of tooth space of gear shaftand centerline of gear teeth and the two lines should be kept parallel each other during the course ofassem bly, so the intervening am ong teeth can be avoided. We keep the above tw o lines separately par-allel w ith fr inge lines of mount w ith Parallel restriction relation, so the tw o lines may be parallelmor e. T hereby, gear teeth cannot intervene during the course of engagem ent.We complete three-dimensional entity model of the m ain components of r educer . Then, w e m akemovem ent emulation for it. Fir st, establish movement analysis case, and gear shaft and bearing insidetrack is link 1, and shaft, gear, fixed-distance loop and cor responding bearing inside track is link2.Then, set up Joint for movement unit, namely set up Revolute betw een gear shaft and gear separate-ly. At last, set up Compound -Gear of revolute1 and 2. Select Kinematic/ Dynamic Analysis in Ani-mation, and input T ime and Step, w e can make movem ent emulation for reducer .Reference: 1 Guangli Zhang, Peng Zhang, Xue Hong,