BAI 7: CAT REN
Gi6i thieu:
Bai nh~~ cung c~p cho h9c sinh nhfrng ki€n thuc v~ c~t ren thu(>c linh vvc ngu(>i trong ngh~ Bao tri h~ th5ng thi€t bi ca khi ngu(>i trong ngh~ Bao tri h~ th5ng thi€t bi ca khi
Mvc tieu:
- Su dJ.{ng GU:(YC phu:ong phap cdt ren trong gia c6ng ngu(Ji.
N{H dung chinh:
1. Chuc nang cua cac dl)ng Cl) ciit ren
1. Khai ni$m
Trang cac thiet bi ca khf thl m6i ghep bang ren rM thong d1,mg, cac chi tiet ghep ren thong dt,mg nhU' vft, dai 6c dLI'Q'C san xuM hang loc;1t v&i gia thanh rat re. NhLI'ng mot s6 chi tiet ghep ren d$c bi$t phai dU'Q'C gia cong bang tay nhU' cac lo ren tren than may.
0e gia cong ren trong lo (ren trong) ngU'O'i ta c6 mot dt,mg Cl) cat dU'Q'C goi la Ta ro. Ta ro thl,l'c ra la mot con vft c6 cat ranh thoat phoi va tc;1O cac thong s6 cat cha IU'O'i cat. Ta ro tay lam bang thep gi6, phf a cu6i chuoi dU'Q'C phay vuong de k~p len tay quay, tren chuoi c6 ghi cac thong s6 cua ta ro nhU': Kfch thU'&c danh nghTa cua ren, bU'&c ren, v$t li$u lam taro, nhan mac cua nha che tc;1O. Taro c6 the c6 mot cay ho$c mot bo gom hai den ba cay. 0e c6 the cat dU'Q'C ngLI'O'i ta phai c6 tay quay ta ro, tuy theo vi trf lo ren ma ta c6 tay quay thf ch hqp, nhLI'ng tat ca tay quay ta ro deu phai c6 ngam k~p hlnh vuong de k~p len ph~n phay vuong cua chuoi ta ro. (Hlnh 5-11)
Hlnh 5-11 . Taro va tay quay taro.
0e gia cong ren tren trvc ( ren ngoai) ngU'O'i ta dung mot dvng Cl) cat dU'Q'C goi la Ban ren (Phi-de). Ban ren thl,l'c ra la mot con dai 6c dU'Q'C khoan cac ranh thoat phoi va de tc;1O cac thong s6 cat cha IU'CYi cat. Ban ren c6 hlnh dang ben ngoai rat khac nhau, neu la hlnh tron th] ben hong c6 khoan lo de ga ban ren len tay quay, ban ren dU'Q'C lam bang thep gi6, tren be m$t ban ren c6 ghi cac thong s6 cua ban ren nhU': Kf ch thU'&c danh nghTa cua ren, bU'&c ren, v$t li$u lam ban ren, nhan mac cua nha che tc;1O. Ban ren chf c6 mot cai duy nhat cha mot kfch thU'&c ren. Tuy theo hlnh dang ban ren ma ta dung tay quay ban ren tU'O'ng Crng.( Hlnh 5-12)
Hlnh 5-12. Cac kieu ban ren va tay quay ban ren.
2. Ky thu~t
+ Gia c6ng tn,ic ren
- Chuan bi: Gia c6ng tn,ic tron c6 dU'cmg kf nh theo kf ch thU'&c danh nghTa cua ren ( thong thLI'cmg thi dU'&ng kf nh tn,ic nh6 hO'n kfch thU'&c danh nghTa cua ren do phan vat dfnh ren), vat dau tn,ic de khi bat dau cat ren de hO'n.
-Thao tac: ( Hinh 5-13)
. K~p chc;3t tn,.1c ( thLI'&ng de tn,ic a vi trf thang dung). Lap ban ren vao tay quay cho chc;3t.
. Tay thu~n cam lay ban ren tc;1i 6 k~p cua tay quay dc;3t vao dau tn,ic, an nh~ ban ren xuong dau tn,.1c va quay theo chieu vc;3n vao cua ren cho ban ren cat vao tn,.1c khoang 1 - 2 ren .
. Dung hai tay nam lay hai tay quay cua ban ren de thl,lc hi$n c6ng vi$c cat ren, quay theo chieu vc;3n vao khoang 1 vong tron thl tra ngLI'Q'C ra hO'n phan m&i vua cat de be phoi.
. Sau khi da cat xong ren thl quay ngLI'Q'C ra de lay ban ren. * Chu y:
. Phai thU'cmg xuyen tra ngLI'Q'C ban ren de lam b6ng m~U ren va kh6ng bi cat ngLI'Q'C (chay ren)
. De ren thang theo tn,.1c thl can chu y dieu chfnh ban ren vu6ng g6c v&i tn,.1c.
+ Gia c6ng lo ren
- Chu~n bi: Khoan lo c6 dU'ang kinh thich hqp. 0U'ang kinh mOi khoan c6 the dU'Q'C tinh toan theo ly thuyet ho?c tra theo bang. Neu v~t li$u CLl'ng thl ta c6 the cha dU'ang kinh lo l&n hO'n mc)t chut. Vat mi$n lo bang mOi khoet chuyen dung ho?c bang mOi khoan c6 kich thU'&c l&n hO'n.
- Thao tac: (Hlnh 5-14)
. K~p ch?t chi tiet can lam ren. Lap ch?t ta r6 vao can ( chu y dung thll' tl,J' c~y ta r6 trong be) c6 nhieu cay)
. Tay thu~n cam lay o k~p ta r6 d?t ta r6 vao lo, an nh~ ta r6 vao lo va quay ta r6 theo chieu V?n vao cua ren de cha ta r6 cat vao lo khoang 1 - 2 ren .
. Dung ca hai tay nam lay hai tay quay cua ta r6 de thl,J'C hi$n c6ng vi$c cat ren, quay theo chieu V?n vao khoang 90 - 180° thl tra ngLI'Q'C ra hO'n phan m&i VLl'a cat de be phoi.
Kiem tra de) d6ng tn,.1c cua ta r6 Cac bU'O'C cat ren trong Hlnh 5-14. Thao tac cat ren trong bang Ta r6 .
. Sau khi cat xong cay ta r6 trLI'&c, thay cay ke tiep cat l9i cha lo ren d9t yeu cau cua m6i ghep.
ta r6.
Cat ren bang tay la m(>t dc;tng cat dinh hlnh c6 nhieu ILI'O'i cat dong thai tham gia cat nen nhi$t cat sinh ra rat l&n, cOng nhU' cac dt,.mg Cl,! cat nay c6 g6c sau bang O nen ma sat giCPa dl,lng Cl,! va chi tiet r§t l&n. Do d6 vi$c b6i trO'n lam mat la dieu het SLl'C can thiet. NhLI'ng can IU'u y chay b6i trO'n lam mat phai thf ch hqp cho tll'ng loc;ti v$t li$u gia c6ng:
- Gia c6ng ren tren thep ta c6 the dung dau, nh&t, e mun xi deu dU'Q'C. - Gia c6ng ren tren dong va hQ'p kim cua dong th] dung e mun xi. - Gia c6ng ren tren Nh6m va hQ'p kim nh6m thl dung dau h6a. - Gia c6ng ren tren gang th] kh6ng cho chat b6i tran lam mat nao.
* cAc D~NG SAi HONG, NGUYEN NILAN VA cAcH KHAC PHT}C
Cac d,;mg sai hong chinh: - Gay ta r6 terong 16 - Gay ta r6 terong 16