rrv KHOA HOC - C N G NGHE MOT SO KET QUA NGHIEN CIJIU, THIET KE, CHE TAO MAY CAT BAM GOC RA Nguyen Xudn Thiet , Le Khd Trudng , Li Minh Lu TOM TAT Mdy cdt bdm gdc rg dugc che tgo theo nguyen ly hai trdng quay Cdy rg dugc cdi vd bdm nho nen phdn huy de ddng Mdy giiip ngirdi ndng ddn gidi quyet vdn de rdt ldn id gidi phdng mat ddng, tang thdi gian sic dung ddt ilia cho cdc cdy hoa mdu khde Phuong phdp gidi phong mat ddng bdng mdy cdt bdm gdc rg chi phi thdp an todn, khong gdy nhiem mdi tnr&ng, tdng thdi gian sie dung ddt Tren ca sd nghien cuu da tgo dugc mdu mdy budc ddu ddm bdo chdt lugng Tir khda: Mdy ndng nghiep, mdy thu hogch, mdy cdt bam gdc rg SOME RESEARCH RESULTS OF DESIGN AND FABRICATION STRAW STUBBLE CHOPPING MACHINE Nguyen Xuan Thiet ', Le Kha Truong ^, Le Minh Lu ^ SUMMARY The straw stubble chopping machine is made according to the principles of two rotating drums The chopped straw will decompose easily Using the machine helps farmer easily to solve clearance their farmland The period time to use rice land for other crops increase, thus increase efficiency of land use On the basis of studies have created initial model quality assurance Keywords; Agricultural machinery, harvesters, straw stubble chopping machine I DAT VAN DE Viet Nam la mot nudc ndng nghiep, cd dien tich trdng lua hai vu ldn, vific dp dung ca gidi hda ndng nghiep nhihig nam gan day dugc sir quan tam cua nha nuac da cd nhimg budc phat trien Ngudi ndng dan da timg buoc ap dung khoa hgc ky thuat vao san suat, viec tang san lugng, giam thdi gian lim dat, doi hdi khau giai phdng mat ddng sau thu hoach la cap thiet Giai phdng mat dong sdm, ndng dan cd the trdng xen canh cay hoa mau giiia hai vu lua Dau tuong la loai cay thudc hg dSu, cd tinh nang co dinh dam tu nhien, cai tao dat tdt, than cay sau thu hoach diing lam phan, quit dau tuang dung chfi bifin thu'c an cho ngudi hoac gia sue Thdi vu cua cay dau tuong rat ngan, phii hgp vdi xen canh giiia hai vu lua De tai cap bg B12-13 dat vdi nhiem vu chinh thiet ke che tao Hen hgp cat bam gdc ra, lam dat tdi thieu gieo dau tuang lien hgp tren may keo banh hai, nham giai phdng nhanh mat ddng, giam chi phi san suat cho ndng dan n VAT LIEU VA PHUOfNG PHAP NGHIEN CUtJ 2.1 Vat lieu, thiet bi nghien ciiii a) Dgc tinh ca ly tinh cua cdy rg Cay la ddi tugng tac dgng chinh tdi cac bd phan lam vific cua may cat bam gdc ra, vay cac dac tinh ca ly cua cay anh hudng toi chat lugng lam viec cua may Cay la phan goc cdn lai ciia cay lua sau da thu hoach phan bdng, mdt sd dac tinh ca ly ciia cay tucmg ddi gidng vdi cay lua Trong dieu kien tu nhien binh thudng cay cd hinh dang nhu hinh 1, vdi gdc nghieng than cay 6, chifiu cao tu nhien H Trong mgt khdm Ilia, cay liia de nhieu nhanh tao dang xde chii V, gon Than cay cd cau tao hinh dng, dugc phan cac gidng va dugc bao bgc bdi be la Vdi cau true nhu vay, cay lua chiu dugc udn dudi trgng lugng ciia bdng va tac dgng ciia cac bd phan may Chieu cao than cdy rg: Chieu cao than cay phu thudc vao timg gidng lua, dao dgng khoang tir 30 ^50 cm Dirdng kinh thdn cdy rg: Trong mgt khdm dudng kinh than cay cd su khac nhau, phu thudc vao gidng lua, each ' TS Tnrcmg Dai hgc NSng nghiep Ha Npi ^ Vi§n ca di6n nong nghiep va C6ng nghg STH ^ TS Tnrong Dai hpc Nong nghiep Ha Noi TAP CHI CONG NGHIEP NONG THON - SO 11 2013 21 LC KHOA HQC - C N G NGHE thitc gieo trdng, cham sdc va muc dp de nhanh cua cay lua Dudng kfnh cay ciing thay ddi thu nhd d4n tir gfic tdi bdng, trung binh 4-8mm III LU*A CHQN NGUYEN LY VA TINH TOAN CAC T H N G S 3.1 Lva chgn nguyen ty lam vifc Qua phan tich cac ket qui nghifin ciiu bd ph|n cat theo nguyen ly tam ggt quay- dao cat co djnh, kfit hgp vdi ly thuylt cat cd tdm ke cac may bSm thdi, nhdm nghifin ciiu dfi xuSt mo hinh may cSt b5m gdc kifiu tr6ng quay Sa dd nguyfin 1^ c^u tao thfi hi^n trfin hmh Hinh Hinh dgng khdm rg Goc nghieng a trgng thdi ttr nhien: Qua khao sat trfin ddng cho ket qua dac thdng ke trung binh =10''-^12,5'' Do dm cua thdn cgy thdi diem Ihu hogch: Vao thdi difim thu hoach, tiiy thufic thdi Hlnh Sa dd nguyen ly cdu tgo tifit, km dao dgng tir 20 -^25% may cdt-bdm gdc rg kieu trdng Mat cdy: 450-5-720 cay/m^ (Liia gieo sa) 1- Dao c3I; 2- Tim kg; 3- Tr6ng quay; - Butong djnh vj v^ dieu chinh chlSu cao cSt; - Xylanh thiiy 1|^; - Dao bam; He so ma sdt gitta thdn cdy vd vgt lieu chi tgo:7 - C ^ h gat; - DOng co thiiy l^rc; o - G6c cua tam ke; Phu thufic nhieu vao am, tic cac cdng - G6c nghign^ trung binh ciia cSy so vdi phuong thing dimg; Vm - van toe tien ciia miiy; h - Chieu cao g6c r? sau cit; trinh nghien curu cho thay he sd ma sat giiia H - Chilu cao goc r? tmdc cat; a - Khoang cich gifia cic than cay va thep (0,39- 0,6), vdi vai bait cao su dao b3m (0,7-1,3) He sd ma sat ndi cua than cay phu May cat bam gdc thirc hifin hai nhiem vu thuge vao gidng lua, song khac biet khdng dang chinh la cat va bam ngan gdc cac doan kfi, cd thfi lay bang 1,8 ngan May lam vific voi ba cdng doan chinh la: Chi phi ndng lugng keo dut dgc thdn cgng ram: cat, va va bam ngan May gdm bd phan cat, bd Cdng dfi keo ddt dgc than cgng ilam khoang phan va va bam ngan gdc Bg phan cat cd hai 51-58xlO-^J chi tifit chinh la tSm ke (2) va dao cat (1) lap b) Thiit bi trfin trdng quay (3) Bd phan va va bam gom cd May keo banh ldp 50-80 HP cac canh gat (7) lap trfin trdng quay thuc hifin 2.2 Phirong phap nghien cihi vifc va va dua g6c dS dugc cat vao bd phan - Thu thap va xir ly thdng tin; bam, tai dSy cd cac dao bara (6) b6 tri song - Phan tich lira chgn nguyfin ly, qua dd thifit song vdi dfi th\rc hien bam ngin gdc lap cac bifiu thiic, cdng thiic tinh toan xac dinh theo nguyfin ly canh gat quay, dao cd dinh cac thdng sd va chfi lam vific ciia cac bg May cat b5m gdc dugc lifin kfitttudcmdy phan Sir dung cac cong cu ho trg thifit kfi may kdo thdng qua cac Bulong (4) Gdc nghieng ciia nhu phan mfim Word, Exel, Inventor, autocad tam kfi cd thfi thay ddi nhd xilanh (5) Chieu cao dfi md phdng va thifit kfi cac bd phan lam vific; ciia gdc sau cat cd thfi dugc dieu chinh - Kfit qua dac cac sd Hfiu thi nghiem dugc thdng qua cac bulong (4) va xilanh (5) xir Iy theo phuong phap thdng ke toan hgc Chifiu dai cua cac doan cit phu thudc vao khoang each giira cac dao bam 22 TAP CHi CONG NGHIEP NONG THON • SO 11 - 2013 KHOA H O C - CONG NGHE 3.2 Lua chon va xac dinh mot so thdng so Can cu vao sa dd nguyen ly va tham khao tai lieu, chgn mgt sd thdng sd chinh: Dao cdt Dao cat chgn la loai dao cat cd chdu, buoc dao tr= 76,2mm Hinh dang va kich thudc thfi hifin trfin hinh Dao dugc lip trfin dia quay cd dudng kinh dinh dao 650 mm Sd lugng dao lip tren mdi dia la 6, thfi hifin frfin hinh A5 qix -^ Hinh Van tdc tgi diem Mciia dao vdo vdt thdi Hinh Dao cdt Hlnh Bgphgn cdt bam gdc rg 1- Bien dgng dao bam; - Dao cit; - Canh gat; - Dao cat co djnh; - Phan b6 cay r^ trSn cinh g^I; Do - Dudng kinh trang; Dl - Dudng kinh dTa dao cat Xdc dinh bien dgng dao bam Nguyfin Iy lam viec: Khi canh gat chuyfin ddng, cac canh gat hai bfin dao cat thuc hien nhifim vu day va ep khdi vira di vao canh sac cua ludi dao vira trugt dgc theo dao, dd qua trinh cat dugc thuc hifin Qua trinh cat d dao cd dinh la cat trugt, vay phai dam bao cac difiu kien vfi cat h-ugt, dfi giam lire cat thi gdc trugt phai ldn hem gdc cit tnrgt Bien dang cua dao bam dugc xac dinh nhu sau: TAP CHi CONG NGHIEP NONG THON - SO 11 • Ta xet mgt chit difim M chuyfin dgng vdi van tdc CO vach hfin mat phing cit mdt q i ^ dao dudng cong cho dudng cong cit tit ca cac tia xuat phat tii mgt diem dudi ciing mdt gdc Lay O lam tam tga do, phuang trinh ciia dudng cong xac dinh tga cue R va cua mgt difim frfin bfi mat cua dao cat Qua hinh ta thay : Chat difim tai M cd tga cue: R va s Chat diem tai M[ cd tga cue: Ri=R +AR, si= s +A s Tir dd suy ra: AR-R,-R=M,Q, A5s^5si-5s Nfiu giua phuang phap tuyen n-n ciia dudng cong tai difim M va vec ta R la (p frong mdt gidi han rat nhd ciia AR thi gdc MjMQ dugc coi la (p Nhu vay, xem tam giac MiMQ la tam giac vudng tai Q cd canh gdc vudng M|Q dugc xac djnh: MiQ=MQ.tangcp^MQ.tp (cp be), ma MiQ=AR va MQ=RA s, tir dd ta suy ra: AR-R.A5s.cphay ARyR=A5s.(p TdR I T - I dS R= fi,/"'"'''' In -^ R = R^e"' R -•25**-^45** (1 + / / g r ) - he sd dac tinh cua dae q - luc cat rieng tren dan vi cua canh sic ludi dao trfin vat thai (^o^50-^120N/cm ddi vdi ram frong trudng hgp chat bd r