NGHIEN CUfU TRAO D O I NGHIEN Cifu VA THIET KE MAY PHAY CNC RESEARCH AND DESIGN OF CNC MILL MACHINE KS.TrUtfng Van Hpi, TS Nguyen Trpng Doanh Viin Co khi, TrUdng Dai bpc Bach khoa Ha Noi TOM TAT Viec thiet ke mdy CNC tgi Viet Nam dd vd dang Id vdn dequan trgng cdn phdi nghien cdu, bdi vi cdc nghiin cdu linh vUc ndy chUa dap dng dUdc viec ldm chu cong nghe CNC Cot loi cua mdy CNC Id cdc true chuyen dgng, bao gom cdc hi ddn dgng vd he thdng diiu khien CNC Thiet ki'mdy CNC chinh la thiet kehe thong dieu khien cho cdc true chuyen dgng chinh cua mdy Bdi bdo ndy de cap din nhdng van di cd bdn thiet ke mdy phay CNC phuc vu nghien cdu vd ddo tgo ABSTRACT Design of CNC machine tools in Vietnam is a very important problem for research, because the actual research in this field are not answered to requirements for mastering of CNC technology The core of CNC machine is composed of actionners and CNC system This paper deals with main problems in designing of milling machine for research and education goal I.GICflTHIEU Miy phay CNC Ii m i y phay dUpe diiu khien tU dpng bang h i thong dii'u khii'n so CNC Chung dupe sd dung rpng rai gia eong cic be mat dinh hinh phdc tap, doi hoi cd dp ehinh xac cao Trin cP sd ve kich thUde, hinh ding cua sin pham, eo the lap trinh bang tay hay lip trinh tu dpng de tao cac dudng ehuyen dao Chuyen sang thinh quy dao chuyen dpng tren khong gian chieu Cau tao chung cua m i y phay CNC bao gom toi thii'u true chuyen dpng tao n i n b i mat 3D vi mpt true ehuyen dpng cua dao True chuyen dpng cua dao dUpe diiu khii'n vdi toe dp xac dinh, nin he thdng dii'u khiin khong q u i phdc tap Ba true chuyen dpng X, Y v i Z l i ba true quyet dinh den chat lupng v i dp chinh xic cua miy CNC Hai chuyen dpng X, Y dupe thUe hien bdi ban hai tpa dp X, Y, tao ehuyin dpng eua ban miy theo hai phupng \ai6ng gde vdi true dao True Z lai la true dUa dau dao tiin lin hay xuong theo yiu ciu cua be mat gia eong M6 hinh mot true cbuyi'n dpng cua bin miy dUpe bii'u dien tren hinh TAP CHf CO KHf VIET NAM 1, DODECOSWO [I]Heti»og(to Hinh I Cdu tgo mgt true chuyen o cita mdy phay CNC V Sd +2 (Thing I +2 nim 2013) NGHIEN CUfU-TRAO D I (3) MO HiNH D O N G LVC HOC CUA TRUC Z Chuyen dpng quay cua true chinh dUpe thUc hien bdi dpng cP servo chieu, hop so va true mang tai Mo hinh dong lUc hpe cua true dupe bii'u dien tren hinh Bin may dUpc dieh chuyen bdi true vit me - bi Gia thiet ring khdp noi gifla dpng ep va vit me - bi hoan toan edng va ehuyen dpng hai chiiu khong co khe hd Can thiet phii xiy dUng cic phUPng trinh dpng lUe hpe cho true chinh eua miy Cae phUOng trinh the hien ban ehat vit ly eua mpt true ehuyen dpng Chung se giup viee dii'u khii'n chinh xae tdc dp v i vi tri cua true de thUe hiin viec gia eong ehinh xac cic biin dang can thiit (4) vk c = (5) Vdi T^ - mo men keo eua dpng ep, C^ - he so cin eiia dpng ep, - toe dp quay cua true dpng CP, 0) - m o men truyen sang true mang tai, J^- Mo men quan tinh eua true dpng cP, 6_^- vi tri gdc cua true dpng eP, M_.- mo men eat, N- d so truyen cua hop giam toe, to - toe dp true mang Ham truyen phan diin eua dpng cP dupe dpn giin hda hang so thdi gian T nhd: F„(s) (6) j } Vdi R - diin trd thuan eua ro to, Kt la hang so mo men keo cua dpng cd, T - hang so thdi gian cua mach diin Hop gidm tdc Hinh He thong dieu khien toe dUdi tdc dgng nhiiu Mc Ham truyen cua thiet bi dieu khien: Fpw(s)= Hmh Mo hinh dgng luc hoc cua true quay nhat la: k^+kj.s-\-ko/s (7) Ham truyen cua he thong vdi dau vao thiJ , h.- , f " i i w - 7— , %(^ ^ y°i H i thdng die'u khien servo cho true chinh eo dang nhU tren hmh vOi Me la tae dpng nhieu Gia thiet la he thong dan dpng eo dp cdng vdng eao, vi mo men can ti le vdi toe dp gde, thi ta si cd eae phupng trinh dong lUe hpe nhU sau: : ~c CO -T =1 d (1) Ham truyin eua he thong vdi dau vao thii hai (nhieu): ^ r > _ I'-j.^'^ *" ~ i-Fp.r)(sj^F._is) (^' T^.N-c aJi(ir) = F i i ( s ) t J , „ ( ) + ^ F i ( s ) M , ( s ) uj,=J 9,^M^ TAP CHf CO KHf V I £ T (2) NAM Toe dd cua true mang tii: s a 1+2 (Thing 1+2 nam 2013) ^^^^ NGHIEN CUfU-TRAOD6| MO HINH DONG LlTC HOC CUA TRUC X Mo hinh dpng lUc hpe cua true mang b i n miy X hay Y d i u tUong tU nhau, n i n ta chi xet mpt trUdng hpp l i du Cic phUPng trinh cP bpc bao gom: i„,r-Cm-.: 2^ Wc Van tdc tren dau cua he niy dupe xac dinh nhu sau: i-.(5) = F2i(s).y,„(s) + F22(5)./v(s) (17) Thong thudng cie h i thong diiu khien so, tie dpng cua nhiiu dupe xem la rat nho v i khdng dUpc quan tam NhUng thUc te bii toin may ta thay nhilu d day cbinb li lUc cit Tuy nhien, tie dpng ehi ed anh hUdng thdi gian rat ngin ehuyen td trang thai chUa eat sang trang thai eat Dap dng trin dau la tde dp ed bi anh budng nhUng sau se dn dinh den toe dp yiu eau vi ta sd dung bp die'u khii'n PID cd k h i ning chdng nhieu rat tdt MOT SO KET QUA MO PHONG Hinh md ta kit qua md phdng ve d i p dng cua true X trUdng hpp chuyen dpng khong tai Htnh He thongdieu khien servo toe cua (rue tinh hen :*_ j i ) » « j , : j : c ^ • : ! i i ' ^ • J , - - i ; i -^ - Hinh Ddp iing cua he truyen ddng Ichi tin hieu Id hinh bdc thang vd hinh sin TAP CHl CO KHl V I £ T NAM ••-' :" , ••;_1 , Hinh Ddp dng cua he diingPID tin hieu Id hdm xung vd hdm tuyen tinh 10 phorg loc ao dong Hinh Mo phong toe dong cd Trin hinh la thay doi eua toe dp eua d i p dng dau vao li h i m bie thang Dpng CP diin mpt chieu diiu khii'n toe dp ed ham truyin la he cap dang Chinh vi viy thiet bi dieu khii'n PID sd dung trUdng hpp niy la dieu kien de dam bao dp chinh xic cao nhat Do be thong dieu khii'n d trUdng hpp chi la h i eap 2, nin h i Iuon dn dinh, chi chu y la dap dng cua he thong la h i m dao dpng ^ TAP CHi CO KHf V I £ T NAM • hay khong m i thoi Khi dieu chinh eic h i so ti li K , h i so tich phin K, va h i so vi phin K^ theo phUPng phap Ziegler - Nichols ta si thu ddpc he vdi toe dp dap dng yeu eau v i ed the giim hay lo?i bd han tie dpng cua dao dpng Ta quan t i m nhat den sai so dii'u khien, trUdng hpp la sai sd toe dp: S6 1+2 (Thing 1+2 nam 2013) NGHIEN CUU - TRAO D O I e„ = l i m , , „ e f = l i m „ „ s E ( s ) = l i m ^ [ u , „ ( s ) - M,(S)] (20) Khi ham vao la ham bac thang don vi, thi sai lech tinh se bang 0, tiJc la khong co sai so ve toe Tuong tii nhu vay cho true tinh tien sai so toe dieu khien cung se tien tdi Nhil vay toe dieu khiln se dap iing duoc yeu cau ve ehinh xae KET LUAN Nghien ciJu da xay dung duoc mo hinh dong lue hoc cua may phay CNC, tinh toan cong suat dong CO va thiet ke he thong dieu khien Mo hinh toan hoe xay dung dUOc co the sir dung de mo phong va danh gia chat luong ciia may tren co sd tinh toan va thiet ke Tuy nhien, de viec thiet ke may phay CNC dugc tot can phai nghien ctiu them nhieu van de nhu npi suy ciing viing ciia may, khe hd eac bo truyen CO I h e m vao do, can thiet phai che tao t h i de kiem nghiem thiic te va danh gia miie dp anh hudng cHa dp ehinh xac gia cong phan co len dp chinh xae eua may cung la hudng phat trien va han che eua bai bao, •!• Ngay nhan bai: 15/12/2012 Ngay phan bien: 15/01/2013 Ngiidi phan bien: PGS, TS Vu Ngoc Pi, TrUdng Dai hpe Ky thuat Cong nghiep, Dai hpe Thai Nguyen Tai li^u tham khao: [1] Riels M Linear Control Systems Engineering, McGraw-Hill International Edition, 1995 [2] W.; Chen J: Yang).- Design of servo system for 3-axis CNC drilling machine based on XPC target, Computing, Communication, Control, and Management, 2009 CCCM 2009 ISECS International Colloquium on 8-9 Aug 2009 [3] Tert P.F: Computer numerical controlled drilling machine interfaced toa computer aided design package PhD Thesis 1996- Cape Peninsula University of Technology [4] Nguyen Trpng Doanh, Nguyen Dilc Minh, Thiet ke may cat ranh soin CNC 16 sau Tap chi Co Viet Nam so 5/2012 TAP CHi CO KHi VI$T NAM V S6 1+2 (Thang 1+2 nam 201.11 | ... duoc yeu cau ve ehinh xae KET LUAN Nghien ciJu da xay dung duoc mo hinh dong lue hoc cua may phay CNC, tinh toan cong suat dong CO va thiet ke he thong dieu khien Mo hinh toan hoe xay dung dUOc... danh gia chat luong ciia may tren co sd tinh toan va thiet ke Tuy nhien, de viec thiet ke may phay CNC dugc tot can phai nghien ctiu them nhieu van de nhu npi suy ciing viing ciia may, khe hd... hpn Iuon ed dap dng nhU hinh 5.a Tuy nhien, d dayed dp qua la dieu khong mong muon doi vdi may CNC Chlnh vi de Ioai bd anh hudng nay, ngoai h i thong dii''u khien PID eon phii sd dung bp han ehe