g ^ I-l'"-
L' CCtnu. n a h e - Mdi trii'o'n^;MOT GIAI PH.\P THIET KE \ A L.AP TRINH GIA CONG CAC BIE.N DANG DAC BIET BANG CONG CU CAD/CAM
ASOLITION FOR DESIGNING .AND M-AMFA.CTURING THE SPECLALCONTOLiRS BY CAD/CAM TOOLS
Trdn Ngoc Hai'
Tom tat
Gia cdng ede chi net dang cam phdng. ede hdnh rdng ddc hiei . cd bten dang Id dirdng Acsnnel, hipdxieldit. epiMcldit ..iheo phuang phdp iriiven thdng thuang rdt kho khdn. hien dang chi tiit cd do chinh xdc khong cao
Bdi bdo tnnh bc'iy mdt pliucmg plidp gio cdng.
theo do trudc heiphai thiei Idp phirang irinh md la bien dang chi tiet. sau dd sir dung cdc plidn mem SoliiiWorLs Masleream de ve ldp Irinh gta cdng Ircn may C.NC Ket qua ihu dirac chi tiit cd dg chinhxdccao Diiy lu phuang phdp lien liin dimg vdt cdng nglie san xudl hien dai
Tir khda Thiei ke bien dang, ldp ninh \C.
gia cdng I. D a t v a n d e
Nhimg chi tilt dang cam phdng can day. bdnh rang irong cac loai bom dac biel. mat cdt budng hill .\\clon loc bui kieu Irong iuc. thudng cd bien dang Id cac duimg Acsimel (hinh 1 a.b), cpixicldil, hipdxicloii. dudng cong Iogarit.
Wnh 1 Cam, hien dang Acsimel N'lec gi,i cdng bien dang cac loai chi tilt Uen dnrdng diroc ihuc hien theo phuona phap chep hn^h tru>eii liiong qua cac cam mdu Theo dd cam mau duac ve iren co sd vac dmh toa do cac dilm 'huoc bien dang roi ndi lai. cdch lam nas thilu chmli \ac
\^'i each nep can khac. chuna tdi ihili idp phir.-ng innh mdia bien da:
A b s t r a c t
Maclnning flat cam sliapes and special gears wiiose curves are Acsimel hipoxicloil and epixicioii.according lo traditional methods, ofien causes difficidly and is not higiily accurate.
The arlicle presenis a method of machining whereby w must first set up the ecjualioiu describing die detailed profiles, and llien use sofnvare SolidWorlcs. Masleream for drawing, programming and maehinmg on CNC. The resulls brought about high aceiircicv. This method IS advanced and ngin with modern prochicim technology
Keywords: Design, profiles, programming NC code. Maniifaetiirnig.
phan mem CAD/CAM \ e bien dang chi tilt, lir do lap chuang trinh NC. gia cdng chi tilt iren may CNC. Day la phuong phap tiep can phan anh diing cong nghe san xuat hien dai. Phdn tilp sau day Irinh bdy mdt sd vi du de 1dm rd phuong phap gia cdng.
2. Giai quyet van Ae
2.1. Co-sd toan hgc xay durng phiroiig trinh mo ta cac dird-ng cong d a c biet
+ Md hinh hda binh hoc: Bdn ci it cua mo hinh hda hinh hoc la md id doi Itr ;, ii ' hi?
bdi md hinh todn hoc. d day dli luana I nh hpc Id dudng cong bien dang chi tilt \ mat oan hoc. cd the bieu dien dudng cong dudi dang*
Phuong trinh an - Phuang trinh tudng minh - Phirong trinh Iham so
Vi du: Dudng trdn ban kinh r Iren ma! phang
dang, sau dd su dunsz cdc
-\ - y. tam triing vdi gdc he toa do diroc mo la btri plmong trinh*
r(x.y} = . \ - + y - - r = 0 (1) Neu chi xet nua tren dudng irdn. phifcmg trinh (1) duac Vllt lai: y=g(.\)=(r-.\-)' - (2)
Cung CO the bieu dien phuong Irinh duong Iron duoi d a n g - X T coso. > = r s i n o (3)
Trong \ i du tren, phironi! trinh:( I) duoc goi li phuong trinh i n : (2) la phuong trinh nrima minh- (j) la phuong trinh Uiamsl.
C i n g vein cac vi du khic. c6 the this moi mo hinh hinh hoc deu co the mo t i boi m6 hinli toin hoc. do chinh l i c o so loan hoc cua phuong phip 2,2, Cac chu-c nang thilt ke hien dai cOa phan mem CAD,
Vol kha nang tinh toin. thilt k l ril manh. phin mem CAD nhanh chong .xic dinh. ve bien danz chi tiel cho boi phuong trinh a dang: i n . tucmg njinh Iham so.
Die diem c i c phuong trinh mo ta bien dang.
- Phuong trinh in khi thuc hien duoc d l hinh tuin tu (khong ndi duoc Iheo trinh tu toa d6 cic diem thuoc bien dang) - la c h i c nang quan trong cita do hoa dien loin ^ " ^ - Phuong trinh tuong minh d l dang chu\en dli l.hinh phuong trinh in ha> phuong trlnh tham s l Mitroe diem chinh l i kh6ng the dilu khiln dudna cong khep kin hoac dutjng thing d i n g .
- Uu diem noi bat ciia phuong trinh tham s6 m6 la bien dang l i du- duong cong Ferguson, diron..
Bezier. duong B-spline dju .. li m6 la chinh xac hon bien dang ehi liC-t va dac biet la phin mim CAD de dang doc si, s i K s6 lieu t i phirona trinh tham so Daj chmh l i K do ta chon phuone trinh tham so mo l i bien dang chi till gia cong.
2.3, Qui trinh thilt k l >a lap trinh gia cong tao hinh theo cong nghe CAD/CAM
Hinh 2 li so dd qui trinh Ihill k l \ a aia cdna lao hmh theo cong nghe CAD C.^M
Ixho,! hoc ( d n a .^,hc - .Mdi i r u i i n g g a Didm khac hidi co ban so \m cdng nghe aia cong tni\ en thdng ia:
-\'iec lao miu ihu cdng duoc tha\ bina md hmh hda hinh hoc t i gia n-j cua miu 3D
- -Man chep hmh dugc iha> bing md hinh loan hoc - md hinh hinh hoc sd.
- Gia cdng chep hinh duoc Ihax bina aia cdng dieu khien sd (C.AM).
2,4. .\p d u n g
2 4 I Thiel ki vd lap uinh gia cdng biin dgng cam xocn oc ,-lcstmet
^ Gia cdng bien dang chi till cam phing cin da> cd bien dang la dudng .xoi\ dc Acsimel (hinh 3). b u d c a = 1 0 . R =50
Hinh 3, Cam. bien dang Acsimel Thuc hien theo cic budc:
I. Lap phuong trinh tham sd bien dana.
T i phuong trinh dudng Acsimel trdng hi ipa do cue p=a.p. MJi c h i > duong Acsimel lix dutma Iron R=50 iam co so => phuong trinh tham s l duong Acsimel:
^^'isiyiLS
\6\ ^—(., l i dd ion budc i n a \ n gdc 9 Ve bien dang cam .Acsimel
Khoi ddng SolidWorks, chon Sketch, chon Front plane iam mat co so
- O mue Spline, chon Equation Dri
xuit hien bang sau n Cu
1 3-..V^2 : ^ v • 3 1 - , . I
v l
\M^
" - - • .
i\.-
— -
.\ CONC DS SC iO-,\
-.0\
—
t"K.=:iN'
Hmh 2, Qm irinh ihiC-i ke'va gia rang tao hinh ,heo ciine nghi- C,W/CA,yi
ITmh 4. Bien dang c
1 ? H Khoa hiH e n n i i n ^ h e - M n i t r u Q - n g - Chon o Pafarr^ctnc , tir muc Equation nhap phirong Irinh (1) (da iha\ sd) \ a o : \ . >
- Trong Parameters, nhdp gdc: l =0. t,=27r - Chon ' ' . thu diroc hinh \ e bien dang cam Acsmiel (hinh 4} Tiep mc \ e hoan chinh cam.
ghi lai file. \ idu (01 DWG) 3 Ldp Irinh NC. mo phong gia cdng - Khdi ddng Masleream. md fiie{01 DWG) - Tien hdnh khai bdo may, phdi, dao, thdng sd cdng nghe. chon lenh gia cdng (Face, Contour, Pocket ) phii hop Viec thuc hien nhir lap trinh gia cdng CO ban
Chi tiet sau gia cdng md phdng nhu hinh 5
iTinh 5. Cam sau gii cimg md phong
Hinh 6. Cam sau gia cdng tren mdy CNC
- 4 2 Thiil ki ldp tr bdnh I, Kid
-ip trinh gui edng bien dang • •qp
- Cho mot cap bdnh rang vieldit cua bom Kooi (innh 7a). Viet chuang Irinh NC, md phone gia cong bien dang chi liet. bilt cung A IB. cunu
^-^UU Ouong h.po\icl6iL cuna B2C, cun^ D4A Id _'hroni: epiMcldil
Hinh 7a. Cap bdnh rdngxicloits Thuc hien theo cdc budc*
1, Lap phuong trinh tham sd bien dang Tren phuong dien toan hpc. dudng epixicloil, dudng hipoxicldil la quy dao ciia mdt dilm thupc mdt duong Iron khi dtrdng trdn dd lan khdng mri;n tren mdt dudng trdn cd dinh khac. Dudng Iron ian goi la dudng trdn co sd. dudng trdn cd djnh goi la dudng trdn djnh hudng.
N l u hai d[rd*ng trdn tiep xiic ngoai thi quy dao cua diem la dudng eplxicloit, nlu hai dirong trdn tiep xiic trong thi quy dao ciia dilm la dirdng hipdxieldit. Hinh 7b la mdt phdn bien dang chi tiet (cung B2C) dugc ve theo phuong phdp truyen thdng (khdng trinh bdy each ve).
4- .Xuat chuong trinh NC gia cdng{irich) iNC FILE - C \NG(X-HAh MCAMX5\MILL\0I KC) N100G2LN!02GOGI7G49GSOG90.
NI04TI
5 Gia cdng tren mdy phay CNC - Diing chuong trinh NC mdi lap, gia cdng tren ina\ CNC, thu dugc sdn phdm (hinh 6)
Nhan \el So vdi phuong phap gia cdng chep ilinh lru>en ihdng. san phdm co:
- Be mat gia cdng chmh xac. tinh xao lion - Sai s6 kich Ihudc. hinb ddng. \ i tri lucmg quan giua cdc mai nho ban do khdng phai sir duna cdc cam chep hinh .
_ - Thdi gian thuc hien ihuc hien quy irinh thilt kc. gia cdng tao hinh giam
IFinh 7b. Bien dang du&ng iplxicldiis Viec xdc dinh cac diem M^ j, ve bien dang chi tiet rdt phuc tap nhat la khi tang M^^ d l tang dp
chinh xac bien dang. , De khdc phuc, lir khai niem v l su hinh thanh
cdc dudng epixicldit, hipdxieldit ta lap diriTC i phuong trinh md ta bien dang:
- Cung A1B, cung C3D (dudng hipdxieldit)
(2)
- Cung B2C, cung D4A (dudng epixicloil)
.""•"""•' ^"-y- (3)
i = l « , . i s » k , -,..iiiCi22_ip
Slf 23. thdng 9/2016
- Tinh gdc a. (I, chdn cung A I B . B2C: dim- cong thirc*
Ii 3 f j
2. Ve bien dang cung A I B . B2C.C3D nhu sau:
Khdi ddng SolidWorks, chpn Sketch, chpn Front plane idm mat c a sd.
; d muc Spline, chpn Equation Driven Curve, xuat hien bang sau:
Bg
n u i ^ T a . t i i . ^ ^ . . CEMER
Vt tl
' 2 37 5-*nCt)-7.
r p . p
!•«
S-OBtS-B
Bl lil
pJ[Spr««
r £ F Equation Onvm Clave
^ ! Irt Splirw
Hlnh 8. Bien dang rang xlcloll - Chon Parametric, trong Equation lin luot nhap phuong i i n h (2). (3) (da thay sii) vio- x , y da v e c i c c u n g A I B , cung B2C... ' '
Trong Parameters, tai t,, t, nhap c i c gdc- (0 „it/2). (,il2„„), (K„3M), (3i/4:.2i) di lin luot vc cac cung A I B , B2C, C3D. D4A.
- Chon •^. thu duoc hinh ve bien dang rang xicldit (hinh 8). ghi lai file, vi du (02 DWG)
3. Lap trinh NC, md phdng gia cdng - Khdi dong IVIasteream, md file (02,DWG) - Tien hinh cac budc tiep theo nhu vi du I Chi tiet sau gia cdng mo phdng nhu hinh 9
K h o a h o c C o n i ; n g h e - M o i i r i t a n g ^ H 4. Xuit chuong trinh \ C gia cdng (trich) (S'CFILE-C,-.\GOCH.4l-.\lC,4,M.\5HIILLm,\iC) M 00 G21 :NM 02 GO G17 G40 G49 G80 G90;
N6310 G28 XO. YO. AO., N63 12 M30.%
2.4,3 Thiet ke, gia cdng chi tiit cam phdng cd bien dang la dirdng CacdtdU
+ Viit chuang i i n h NC, md phdng gia cdng bien dang chi tiet cam phing bien dang la dudng Cacdidit, cho a=26, cam day 16mm.
Thuc hien theo 5 budc-
I. Thiet lap phirong trtnh tham sd bien dang T i phoong trinh dudng Cacdidit ttong he toa do cue p = a(|-fcos(p), vidl'
dang tham sd-
[j: = a c o s ^ l + eosp) [3' = o s i n ^ l + c o s ^ )
i phirong h-inh dudi
(4) d day- a =26; (p = 0 .251 2. Ve bien dang dudng Cacdidit
- Khdi ddng SolidWorks. chon Sketch, chon Front plane lam mat co sd.
- 0 muc Spline, chon Equation Driven Curve, xuit hien biing sau:
ciBS^-ik=a.2.
Hlnh 9. Chi till sau gia edng mo phdng
Hinh 10. Dudng Cdediod - Chon •••Parametnc, ,i, muc Equation nhap phuong trinh (4) (da thay sti) vio- x . y_
- Trong Parameters, nhap gdc. 1 = 0, I.=2K - Chpn -^.thu dugc hinh vii dudng Cacdidit (hinh 10) G h i l a i f i l e v i d u ( 0 3 DWG) "
J Lap trinh NC. md phong gia cdng
Si 23 ihiui
~9/20l6 1 3 ^
B M K h o a hoc C o n g n g h e - Mdi Irtfd'iig -Khoi done \I.1M,
- Tiiin lianh kliai b vd cdng iigiic. clion li Pockci ) phii hop
j . j - n . n,i file (03 DWG) 10 ]ii,i\ phdl. dao. cac tlldiig
ih gia cdng (Face. Contour.
I ,cp IUC nhu lap Ilinli gia cdng CO ban
Chi tiel sau gia cdng md phong nhu Hinh I
H'lnh 11, Cam Caedlait sau gia e 4 Xuat chuong Ilinh \ C gia
''•C FILF.-C\\GOCIHI.MC-tyLY5-MlLLi03 SC)
N40:0 G2S XO YO AO N4022 M30, 5 Gia cdng Ircn mi> pha\ CNC Hinh 12 li chi net dang diroc gta cdng tren mi>' lir chuong trinh NC vita linh loan
img tren mdy AOI:.! XHl.L
Bai bao da li inh ba> phuong phap lap iriiili \ c liico bidn dang, gia cdng mdt sd dang ch: ndt die biet Phin quan trijng nhil cua phuong phap Ij chujdn nV md hinh hinh hoc cua ddt liiong sanu xi> dung md hinh loan hoc. thtel lap plnrmgirini, tham sd md la bien dang chi net
Vide st:r dung cic phin mem Soliduorks.
Masteicam la dira tren tinh nang ndi bai \'d CAD/
CAM cua mdi phin mem nhd dd vitic linh toin ve. lap trinh NC duoc thuc hien nhanh chdng,
Phudng phip lap irinh theo bien dang cho phep Ciic ky sir cdng nghe chii ddng trong lap irinli gia cdng cae dang chi tidt phirc tap Diy la phuong phip lien liJn, diing vdi cdng nghe'san xuil hien dai
Kel qui. Sin pham sau gia cdna theo cong nghe CAD/CAM cd di> chinh xic, dd tinh sal cao hon, Bien dang sin phim khdng bi sai si in d.ip do hicn tuong cam miu chep hinh bi mon ,, nlur gia cdng thed phuong phap truyin thdng.
^lldl gian Ihuc hie ilinh, gia cdng giim
-1, HutVng p h i t trien tiep theo eiia de lai Thiet ke lao hinh, gia cdng cae chi lidl dang cam khdng gian, mai cong 3D bing cich xaj"
dung cac phuong trinh toin md la bien dang ihco Ida dd can, loa dd iru. tu dd sir dung cac phan mem CAD/CAM hd tro ve lao hinh, lap trinh NC gia cdng.
Tinh toin. idi uu hda cic ihdng sd chi do cii (s. v, I) li-oiig q u i tl inh gia cdng
trinh thicl ki i^o
T i i lieu tham khao
h i M n i h l t m h m , Cong nglie CriaCAM NXB Khoa hoc Ky thual.
2011. Thuc hdnh thiil ki v - ' ^ ^ I U M I ' V " , ™ ' ! ' " " " " ' " " ' • ^ = " ' ^ " ' ' * ' • = "T'^'. Mni. Van H:
' ' " ' " " " ^-^15 ^.lioa hoc Ky Ihuiit, '•' ^ e - l l a . 2000 Boi top ngm en li may NXB Khoa Hoc Kv .hni, I "'1 u l l ! " " " " " - " " " " ' " " " ' ' " " ^ ^ ' " >^™ Da, hoc Oudc gia Ha Not.
' " . ' • ' , « Uiieo . , ; IZ r IV '• x'!,"„V°,"' " ' " • - " " •W""c'-c-"», - Pliiin mim thiit killing nghi C-ID
" ' " ^-^B Khoa hoc K-T thuit
in,i; 9/2016 0
