105

CHNG V

MAY GIA CONG BANH RANG

H. V.1. Cac dang banh rang gia cong

106

Phi hp cc chuyn ng to hnh c ng trn v ng thng giacng cc b mt phc tp ca bnh rng

I. CAC PHNG PHAP GIA CONG BANH RANG

Co hai ph ng phap gia cong banh rang.

I.1. Phng phap nh hnh

La ph ng phap ma cnh ca li ct trng vi ng sinh chi tit gia cng.

egia cong bang ph ng phap nh hnh can co :- May phay van nang.- au phan o co a chia hoac khong co a chia.- Dao phay modul co hai loai : + Dao phay ngon modul.

+ Dao phay a modul.

H. V.2. Phng phap phay nh hnh n gian

H. V.3. Cac dang phay nh hnh

107

Ve nguyen tac khi gia cong banh rang co modul m so rang Z can phaico 1 dao phay rieng. Nhng v iu kin ch to kh khn nn ngi tach to theo b v chap nhn c sai s ve bien dang rang

Dao phay c tieu chuan hoa thanh hai bo :Bo 8 : gom co 8 dao c ky hieu 1, 2, ..., 8.

Bo 15 : gom 15 dao c ky hieu 1, 121 , 2, 2

21 , ..., 8.

So lieu dao 1 1 2 2 3 3 4

Bo 8 ; S rng 1215 1416 1720 2125Bo 15 ; S rng 12 13 14 1516 1718 1920 2122

u iem :+ Khong can phai co may phay chuyen dung.+ Dao phay modul c che tao de dang.

Nhc iem :+ o chnh xac thap (co sai so do bien dang cua dao, do phan o).+ Nang suat thap.+ So l ng dao phay modul rat ln. Chu yeu gia cong banh rang trong san xuat n chiec.

I.2. Phng phap bao hnh: La ph ng phap gia cong banh rang nhac lai s ankhp gi a banh rang thanh rang hoac gi a banh rang banh rang.

So lieu dao4 5 5 6 6 7 7

Bo 8 2634 3554 55134Bo 15 2325 2629 3034 3541 4254 5580 81134

108

a. Da vao nguyen ly an khp banh rang - thanh rang: trong o thanh rang ongvai tro la dao ket cau may ph c tap va cong kenh.

Thay dao co dang thanh rang bang dao co dang truc v t goi la dao phay lantruc vt may phay lan rang.

May phay lan rang co cac chuyen ong tao hnh- Chuyen ong chnh : chuyen ong quay cua dao n d.- Chuyen ong bao hnh : chuyen ong quay cua phoi n p.

Moi quan he gi a chuyen ong quay cua dao va phoi.

k1 vong dao

z

1 vong phoi.

1 vong dao z

k vong phoi.

Chuyen ong chay dao la chuyen ong chay dao ng (da o se chuyen ongtnh tien theo ph ng thang ng)

b. Da vao nguyen ly th haiNguyen ly an khp banh rang banh rang.

Khi ng knh chia rang ln so vi thanh rang, dao co dang thanh rang se c thay bang dao co dang banh rang, dao co dang banh rang goi la dao xoc may xoc rang.

H. V.4. Nguyen ly gia cong bao hnh

109

+ Chuyen ong chnh la chuyen ong tnh tien thu hoi cua dao xoc n htx.+ Chuyen ong bao hnh : gom chuyen ong quay cua dao n d va chuyen

ong quay cua phoi v i moi quan he.

dz

1 vong dao pz

1 vong phoi.

zd so rang cua dao xoc.zp so rang can cat cua phoi.

1 vong dao p

d

z

z vong phoi.

Chuyen ong chay dao h ng knh : la chuyen ong tnh tien cua ban maymang phoi theo ph ng h ng knh nham gia cong het chieu cao rang (h). h = 2,25 m. (vi m la Modul cua banhrang gia cong)

So sanh hai loai may phay lan rang va may xoc rangMay phay lan rang c s dung rong rai hn v co nang suat, o chnh xac

cao.Tuy nhien may xoc rang c s dung e gia cong trong cac tr ng hp ma

may phay lan rang khong the th c hien c: gia cong banh rang bac, gia congbanh rang trong.

II. MY PHAY LN RNG

II.1.Nguyn l gia cng ln rng:My ln rng l my gia cng bnh rng theo phng php bao h nh, lp li

chuyn ng ca banh rang va thanh rang trong o mot ong vai tro la dao, motong vai tro la phoi s an khp nay la s an khp c ng b . Nh ng theo nguyenly nay se gay ra cac tr ngai sau

1- Chuyen ong chnh e gia cong c la chuyen ong tnh tien k h hoi, vvay khi chuyen sang thiet may, chuyen ong kh hoi kho co the hiencac c cau nguyen ly may, ben canh o cac thong so phu hp vi cacieu kien kch th c gia cong kho at yeu cau e ra.

2- Chuyen ong kh hoi lam thi gia phu gia tang, nang suat giam.3- Cac thong so ve so rang, modul dan en chieu dai dao cat thay oi cho

nen kho che tao dao. T o nguyen ly gia cong banh rang c thay oi bang ph ng phap ankhp banh vt va truc vt bien chuyen omg kh hoi h u han thanh chuyen ongquay tron v han cua truc vt, mot ong vai tro la phoi mot ong vai tro la dao, s an khp nay la s an khp c ng b c .

110

II.1.1. Gia cong banh rang tru rang thang

Cac chuyen ong tao hnh gom :+ Chuyen ong quay cua dao n d.+ Chuyen ong quay cua phoi n p.+ Chuyen ong chay dao ng S .

Moi quan he gi a dao va phoi khi gia cong :

Dao

Chi tit

Chitit

Dao

S nguyn l gia cng bng phng php bao hnh

H. V.5.Chuyen ong tao hnh gia cong banh rang bang phng phap bao hnh

111

1 vong dao z

k vong phoi.

Vi cac banh rang co m 3 co the gia cong trong mot lan.Vi cac banh rang co m > 3 chia thanh cac b c gia cong tho va ti nh.

e am bao l i dao phay luon trung vi h ng cua ranh rang ta phai quaytruc dao mot goc bang goc nang cua dao.

II.1.2. Gia cong banh rang tru rang xoan

Cac chuyen ong tao hnh

+ Chuyen ong chnh chuyen la ong quay cua dao n 1+ Chuyen ong bao hnh la chuyen ong quay cua chi tiet n2 v chuyn

ng dao phay n1.+ Chuyen ong chay dao ng S 1 (la chuyen ong cua dao theo ph ng

thang ng).+ Chuyen ong vi sai la chuyen ong quay them hoac bt i cua phoi tao

ra ng xoan n3. Chuyen ong nay do c cau vi sai th c hien goi la chuyen ong vi sai.Chuyen ong vi sai phai am bao

1 vong phoi TS

kz vong dao.

z : So rang can gia cong.k : So au moi cua dao.S1 : Lng chay dao ng.

T : B c xoan.

n

n1

n23

S1

H. V.6.Cac chuyen ong tao hnh gia cong tren may phay lan rang

112

sinZmT n .

Cac ieu chnh can thiet khi gia cong banh rang xoan

- ieu chnh goc quay cua truc dao = a1 Dau (-) neu chieu xoan cua dao va banh rang gia cong cung chieu. Dau (+) neu chieu xoan cua dao va banh rang gia cong ng c chieu.

- ieu chnh khoang cach A gi a ng tam dao va phoi e am bao chieucao rang h (h = 2,25 mm).

II.1.3.Gia cng bnh vt

+ Chuyen ong chnh la chuyen on g quay cua dao nd.

H. V.7. ieu chn hgoc dao cat phu hp vi goc xoan

H. V.8.Chuyen ong ta o hnh gia cong banh vt

113

+ Chuyen ong bao hnh (chuyen ong phan o) la chuyen ong quay cua phoi.

1 vong dao z

k vong phoi.

+ Chuyen ong chay dao h ng knh S 2 la chuyen ong tnh tien cua banmay mang phoi theo ph ng h ng knh.

Ph ng phap chay dao h ng knh co u iem nang suat cao song dao monkhong eu, v vay ng i ta co the dung ph ng phap chay dao tiep tuyen .

Chay dao tiep tuyen la chuyen ong tnh tien cua dao theo ph ng doc tructiep tuyen vi banh vt can gia cong, tat ca rang cua dao eu hoat ong l ng mon eu nh ng nang suat thap.

II.2. MAY PHAY LAN RANG 5E32

II.2.1.S kt cu ng hc

S

C

ivv

VS

iy

is

ix

Dao

Phoi

H. V.9. S o ket cau ong hoc may phay lan rang 5E32

114

II.2.2. S ng

II.2.2.1. Phng trnh c ban xch toc o

nc . iv = ntc.+ Xch toc o th c hien chuyen ong quay cua dao n d:

n1(1440) dv ni 7218

2525

2525

2525

3535

4832

240126 (vong/ph).

126

dv

ni .

II.2.2.2. Phng trnh xch bao hnh

1vong dao z

k vong phoi.

1 vong daoz

kife

x 9611

4646

2525

2525

2525

1872 vong phoi.

115

fek

Zix

24

Vi 1fe =

5454 . Khi gia cng chi tit c Z160

II.2.2.3. Phng trnh xch chy dao dc trc1 vong phoi Sd (mm/ vong)

1 vg phoi dxs Sti 305

204

1616

1919

3645

242

196 ; trong o tx= 10 mm

is= 103 Sd

II.2.2.4. Phng trnh xch chy dao dc trc1 vong phoi Sn (mm/ vong)

1 vg phoi dxs Sti 305

2520

202

204

1616

1919

3645

242

196 ;

trong o tx= 10mm

is= 85 Sn

II.2.2.5. Phng trnh xch chy dao dc trc

Xch chay dao doc truc

Th c hien chuyen ong tnh tien cua dao theo ph ng doc truc khi giacong banh vt bang ph ng phap chay dao tiep tuyen.

Khong dung c cau vi sai

1vgphoi tS vong dao (quay them hoac bt i).

1 v/ph ts Si 2501

3535

1616

1919

3645

242

196 (mm/vph).

ts Si 25 .

116

Dung c cau vi sai 1vgphoi zm vong dao.

1v/ph zmie

fi yx

2501

3535

1616

1919

36451

130

211

196 (mm/vph).

mk

is3 .

II.2.2.6. Phng trnh xch chy dao ct rnh xon

Khi ct rnh xon,ngi ta khng cho bit bc xon T m cho gc nghing carng , ta c mi quan h nh sau:

Cos =

cos.. m

mm

m

t

tS

SS

T = .cotg = .z.m S .cotg

sin..

coscot.. mzgzT

mkT

z

dc

baiY

25.1

1

1

1

cng thc iu chnhkmd

c

baiY .

sin.95775.7.1

1

1

1 Dau khi hng xon ca dao v phi cng chiuDau + khi hng xon ca dao v phi ngc chiu.