2. Cau tao va nguyen li lam viec cua cac loai may nang don gian.

1. Kich

a. Kich thanh rang co cau tao don gian, hieu suat tuong doi cao, duoc che tao voi suc nang tu 25tan, chieu cao nang 0,30,7m. Tren hinh 1.1 la cau tao cua mot kich thanh rang loai thong dung. Momen tren truc tay quay do nguoi su dung tao ra duoc truyen thong qua mot cap banh rang tru den banh rang dan cuoi cung. Banh rang nay luon an khop voi thanh rang 2 co kha nang truot len xuong nho dan huong cua cac bac truot bo tri tren vo kich co dinh 1. De co ket cau nho gon, cac cap banh rang co ty so truyen tu 4 den 6, banh dan co so rang nho, thuong tu 4 den 6 rang.

1- Than kich; 2- Thanh rang; 3- Dau kich; 4- Ban nang phu; 5- Tay quay; 6- Bo truyen banh rang; 7- Truc cua tay quay; 8- Banh rang lien dia ma sat ben trai; 9- Banh coc; 10- Con coc; 11- Dia ma sat ben phai.

Muon nang vat, quay tay quay thuan chieu, dia ma sat ben phai 11 va banh rang lien dia ma sat ben trai 8 ep chat vao banh coc 9 tao thanh mot khoi. Nho ma sat ma momen duoc truyen den banh rang dan, day thanh rang len. Vat giu o do cao mong muon nho coc ham 10. Khi ha vat, chi can quay tay quay theo chieu ha, khi nay truc 7 dich chuyen sang phai tach dia ma sat 11 khoi banh coc 9 va vat nang cung thanh rang ha xuong do trong luong ban than cua chung. Vat nang tiep tuc ha voi van toc tang dan cho toi khi van toc goc cua banh rang 8 bang van toc goc cua truc 7 do ta quay tay quay thi truc 7 ngung dich chuyen sang phai va khi banh coc quay nhanh hon truc 7 thi no lai ep banh coc 9 vao dia 11 lam giam toc do ha vat cho den khi banh rang 8 quay cham hon truc 7 thi no lai tach khoi banh coc 9 va lai lap lai qua trinh tren.

Loai nay cho phep khong che toc do ha vat rat tot. O nhieu kich thanh rang, nguoi ta con bo tri them ban nang phu 4 dung de nang hang duoi thap. Do luc tac dung lech tam nen suc nang giam xuong con mot nua.

b. Kich vit:

Co chieu cao nang thuong nho hon kich thanh rang va co suc nang den 20 tan va chieu cao nang 0,20,4m. Kich vit lam viec theo nguyen tac truyen dong dai oc.

Cau tao kich vit bao gom dau kich 3 dong vai tro nhu mot o chan co the quay tron duoc. Truc ren vit 2 duoc truyen dong nho co cau banh coc hai chieu co banh coc kep tren truc vit (hinh 1.2). Khi tao chuyen dong cho tay don, truc vit se quay va chuyen dong tinh tien doc than kich. Ren thuong dung cho vit la ren co dang hinh thang va loi dung tinh tu ham cua ren de ham giu vat nang voi goc nang cua ren la 4050.

c. Kich thuy luc co chuyen dong em nhu kich vit nhung co hieu suat cao hon va duoc che tao voi suc nang lon, co the dat den 750t, chieu cao nang 0,150,7m. Nguyen tac lam viec cua kich la ap luc dau tu bom duoc truyen den xy lanh cong tac de nang vat. Cau tao kich gom hai bo phan chinh: bom va pittong-xy lanh cong tac. Vat duoc nang len khi chat long vao xy lanh cua kich va duoc ha xuong nho chat long di qua van xa. Dieu chinh toc do dong chay cung tuc la dieu chinh toc do ha vat bang van xa. Chat long trong kich la dau khoang hoac nuoc pha glyxerin co ti le 2:1. Day chat long vao kich bang bom tay hoac bom co dong co dan dong. Bom gan truc tiep voi kich hoac noi vao kich qua he thong ong dan. Mot bom co the dan dong cho mot hoac nhieu kich .

Hinh 1.3 gioi thieu so do kich thuy luc lien voi bom, dan dong tay. Nguoi dieu khien day tay lac 8 ve ben trai, lam cho pittong bom 1 chuyen dong tu trai sang phai, dau tu thung chua 2 qua van mot chieu 3 vao trong xylanh bom 9, luc nay van ap luc 4 duoc dong lai. Khi day tay lac 8 ve phia phai, pittong bom 1 chuyen dong tu phai qua trai, day dau tu xylanh bom 9 qua van ap luc 4 vao xylanh kich 6 day pittong 5 len tren, luc nay van mot chieu 3 duoc dong lai. Vat nang duoc nang len mot cach gian tiep.

doan theo nhip lac cua tay don bom. Khi muon ha vat, mo van 7 va duoi tac dung cua trong luong vat nang, dau kich se duoc ha xuong. Chat long tro ve binh chua qua van 7.

Kich thuy luc:1- Pittong bom; 2- Thung dau; 3- Van mot chieu; 4- Van ap luc; 5- Pittong chinh; 6- Xylanh kich; 7- Van thai; 8- Tay lac; 9- Xi lanh bom.

2. Toi

a. Toi dan dong tay (hinh 1.4) duoc su dung khi luc keo nho (580kN) va dung luong cap tren tang nho (50200m). Cau tao gom cap (doi khi dung xich) 1, duoc cuon tren tang 2; bo truyen 3, co phanh 4 va tay quay 5. Vat nang Q duoc lien ket voi cap thong qua thiet bi treo vat 6.

b. Toi dan dong bang may. Toi duoc dan dong bang may thuong su dung dong co dien. Toi duoc gan tren khung be de de dang van chuyen, cung nhu dinh vi chong luc keo ngang hoac nghieng. Toi may hay duoc phoi hop voi to hop rong roc (palang cap) de keo hoac nang duoc vat rat nang. Luong cap chua tren toi rat lon, co the den 200400m. Co nhieu loai toi khac nhau nhu: toi mot tang quay hai chieu, toi nhieu toc do, toi ma sat. Tren hinh 1.5 trinh bay mot kieu toi mot tang quay hai chieu dan dong bang dong co dien. Toi nay duoc dung nhieu trong xay dung va o cac bai lap rap. Dong co dien duoc noi voi hop giam toc bang khop noi dan hoi 6. Vanh ngoai cua nua khop noi ben phia hop giam toc dong thoi la banh phanh. Khoi dien tro 8 dung de khoi dong cho dong co day cuon 7 voi 3 den 4 nac dien tro chuyen doi nho hop dieu khien can gat 4.

Dieu kien lap rap cac ket cau xay dung, cac thiet bi nang doi hoi toi phai co nhieu toc do. Cac toc do cao dung de nang tai va ha moc khong tai. Cac toc do thap dung de dat va dieu chinh vao vi tri lap rap.

Hinh 1.4. Toi xay dung dan dong bang tay

1- Cap; 2-Tang cuon cap; 3- Cap banh rang truyen dong; 4-Phanh; 5- Tay quay; 6-Cum moc treo.

Hinh 1.5. Toi dan dong bang dong co dien

1- Be may; 2- Tang cuon cap; 3- Hop giam toc; 4- Tay gat dieu khien; 5- Phanh hai ma dien thuy luc; 6- Khop noi dan hoi; 7- Dong co day cuon; 8- Hop dien tro

3. Palang

a. Palang xich keo tay

Palang xich kieu banh rang su dung bo truyen hanh tinh (hinh 1.7) co ket cau nho gon. Momen duoc truyen tu banh rang keo 4 sang truc dan 9. Nho cac banh rang hanh tinh 7 luon an khop voi vanh rang co dinh 5 gan tren vo nen cac truc cua banh rang 7 lam can 8 quay dan dong cho dia xich tai 2. Palang duoc trang bi phanh tu dong voi mat ma sat tach roi 3. Palang keo tay duoc che tao voi suc nang tu 0,5 - 20t.

b. Palang dien co uu diem la trong luong nho, ket cau gon, do tin cay cao, chi phi bao duong, sua chua thap, de thay the cac chi tiet hong, de su dung, hieu suat cao. Palang dien duoc su dung nhu mot may doc lap hoac lam nhien vu co cau nang trong cac can truc, cong truc, can truc congxon v.v, khi nay no duoc trang bi them co cau di chuyen. Tren hinh 1.8 mo ta cau tao cua mot palang dien co dong co lien tang.

Palang xich keo tay kieu banh rang:1-Xich keo; 2-Dia xich tai; 3-Phanh tu dong; 4- Dia xich keo; 5- Banh rang co dinh; 6- Banh rang trung gian; 7- Banh rang hanh tinh; 8- Can cua truyen dong hanh tinh; 9- Truc dan; 10- Xich tai.

Palang dien co dong co lien tang:1- Dong co; 2- Tang; 3- Ngan phu; 4- Bo lay dien ; 5- Khop rang; 6, 7,10,11- Banh rang; 8- Phanh giu chan; 9- Phanh dien tu; 12- Ro to.

4.Thang nang xay dung

a. Thang nang cho hang (hinh 1.9) thuong duoc dat canh toa nha dang thi cong. Cau tao gom khung be 1, cot 4 tren do co gan cac thanh dan huong, ban nang 7 duoc lap tren gia truot 6 , toi dien dao chieu 3 va tu dien dieu khien 2. Gia truot cung ban nang tua tren cac thanh dan huong nho cac con lan. Cap cua toi dien dao chieu vong qua cac pu li

tren dinh cot va pu li 8 gan tren ban nang, dau cap duoc co dinh tren dinh cot. Cot gom nhieu doan noi voi nhau bang bu long. Tuy theo chieu cao cua toa nha ma co the noi them cac doan giua de tang chieu cao. Khi chieu cao cua cot tren 10m thi phai dung cac thanh giang 5 de co dinh vao ket cau cua toa nha. De tang tinh co dong cua thang nang, nguoi ta lap khung be 1 tren he banh hoi.

Vat lieu duoc nang len cac tang nha qua cac op cua so. De dam bao an toan va thuan tien cho viec chuyen vat lieu qua cua so, ban nang duoc trang bi san day 10 dan dong bang co cau 9 (hinh 6.9,c). Thang nang duoc dieu khien bang hop nut bam. a dinh va day cot phai duoc trang bi cac cong tac han che hanh trinh de ngat dong co khi ban nang den cac vi tri do. Ngoai phanh cua toi dien dao chieu 3, tren gia truot con co bo ham bao hiem de dung va giua ban nangtren cot khi dut cap.

Thang nang cho hang:1- Khung be; 2- Tu dien; 3- Toi dao chieu; 4- Cot thap; 5- Thanh neo; 6- Gia truot; 7- Ban nang; 8- Pu li gan tren ban nang; 9- Co cau day; 10- San day.

b. Thang nang cho hang va nguoi:

Dung de phuc vu thi cong cac nha cao tang, cu the de nang vat lieu len cac tang nha va cai thien dieu kien di lai cho cong nhan. Thang nang loai nay co chieu cao nang dat toi 110m (tuong duong voi nha 30 tang) va co tai trong nang tu 0,51tan. Thang nang loai nay con goi la thang may thi cong va theo ket cau no chi khac thang may o cho cabin nam canh va truot theo thanh dan huong gan tren cot thap con cabin thang may nam trong gieng thang. Theo phuong phap truyen dong co thang nang truyen dong cap va thang nang truyen dong banh rang thanh rang.

Thang nang cho hang va nguoi truyen dong cap co loai dung toi dien dao chieu voi tang cuon cap dat duoi dat nhu thang nang cho hang va loai dung toi dien dao chieu voi puli dan cap bang ma sat.Tren hinh 1.10 la thang nang cho hang va nguoi truyen dong cap voi puli dan cap bang ma sat. Thang gom cot 1 tren do co gan cac thanh dan huong, cac puli 4 tren dinh cot, ca bin 5 co dinh tren gia truot, doi trong 2, toi dien dao chieu voi puli dan cap bang ma sat 6 va can 3 dung de nang cac doan cot khi lap dung va tang chieu cao cot. Cabin cua thang duoc trang bi san day co lan can de dam bao an toan cho nguoi va hang khi boc do vao cac tang. Dieu khien cabin va san day nho cac nut bam trong cabin. Cot duoc neo vao ket cau nha bang cac thanh giang cung de dam bao do cung vung va on dinh. Thang nang cho hang va nguoiduoc trang bi thiet bi ham

bao hiem de giu cabin tren cac thanh dan huong khi dut cap hoac toc do ha vuot qua gia tri cho phep (mot so thang nang con co ca thiet bi ham bao hiem cho ca doi trong ). Thiet bi ham lam viec do tac dong cua bo han che toc do ( loai thang dung toi co tang cuon cap thi khong can bo han che toc do). Ngoai ra thang con duoc trang bi cac thiet bi han che hanh trinh cabin, he thong den tin hieu va cac thiet bi an toan dien khac

Thang nang cho hang va nguoi truyen dong cap:1- Cot; 2- Doi trong; 3- Can lap dung; 4- Puli dinh cot; 5- Cabin; 6- Tang dan dong.