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KHOA HOC - C 6 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 6 nhiem mdi tnr&ng, tdng thdi gian sie dung ddt. Tren ca sd nghien cuu da tgo ra 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 khi 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 ra 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.
' 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
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 ra la ddi tugng tac dgng chinh tdi cac bd phan lam vific cua may cat bam gdc ra, do vay cac dac tinh ca ly cua cay ra anh hudng toi chat lugng lam viec cua may.
Cay ra la phan goc cdn lai ciia cay lua sau khi da thu hoach phan bdng, mdt sd dac tinh ca ly ciia cay ra tucmg ddi gidng vdi cay lua.
Trong dieu kien tu nhien binh thudng cay ra 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 thanh 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 ra phu thudc vao timg gidng lua, dao dgng trong 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
2013 21
LC
KHOA HQC - C 6 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.
Hinh 1. Hinh dgng khdm rg Goc nghieng do a trgng thdi ttr nhien:
Qua khao sat trfin ddng cho ket qua do dac thdng ke trung binh 0 =10''-^12,5''.
Do dm cua thdn cgy trong thdi diem Ihu hogch:
Vao thdi difim thu hoach, tiiy thufic thdi tifit, do km dao dgng tir 20 -^25%.
Mat do cdy: 450-5-720 cay/m^ (Liia gieo sa) He so ma sdt gitta thdn cdy vd vgt lieu chi tgo:
Phu thufic nhieu vao do am, tic cac cdng trinh nghien curu cho thay he sd ma sat giiia than cay va thep (0,39- 0,6), vdi vai bait cao su (0,7-1,3). He sd ma sat ndi cua than cay phu thuge vao gidng lua, song khac biet khdng dang kfi, cd thfi lay bang 1,8.
Chi phi ndng lugng keo dut dgc thdn cgng ram:
Cdng dfi keo ddt dgc than cgng ilam khoang 51-58xlO-^J
b) Thiit bi
May keo banh ldp 50-80 HP.
2.2. Phirong phap nghien cihi - Thu thap va xir ly thdng tin;
- Phan tich lira chgn nguyfin ly, qua dd thifit lap cac bifiu thiic, cdng thiic tinh toan xac dinh cac thdng sd va chfi do lam vific ciia cac bg phan. Sir dung cac cong cu ho trg thifit kfi may nhu phan mfim Word, Exel, Inventor, autocad dfi md phdng va thifit kfi cac bd phan lam vific;
- Kfit qua do dac cac sd Hfiu thi nghiem dugc xir Iy theo phuong phap thdng ke toan hgc.
III. LU*A CHQN NGUYEN LY VA TINH TOAN
CAC T H 6 N G S 6
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 trong cac may bSm thdi, nhdm nghifin ciiu dfi xuSt mo hinh may cSt b5m gdc ra kifiu tr6ng quay. Sa dd nguyfin 1^ c^u tao thfi hi^n trfin hmh 2.
22 TAP
Hlnh 2. Sa dd nguyen ly cdu tgo may cdt-bdm gdc rg kieu trdng
1- Dao c3I; 2- Tim kg; 3- Tr6ng quay; 4 - Butong djnh vj v^
dieu chinh chlSu cao cSt; 5 - Xylanh thiiy 1|^; 6 - Dao bam;
7 - C ^ h gat; 8 - DOng co thiiy l^rc; o - G6c cua tam ke;
8 - G6c nghign^ trung binh ciia cSy so vdi phuong thing dimg;
Vm - van toe tien ciia miiy; h - Chieu cao g6c r? sau khi cit;
H - Chilu cao goc r? tmdc khi cat; a - Khoang cich gifia cic dao b3m.
May cat bam gdc ra thirc hifin hai nhiem vu chinh la cat va bam ngan gdc ra thanh cac doan ngan. May lam vific voi ba cdng doan chinh la:
cat, va va bam ngan. May gdm bd phan cat, bd phan va va bam ngan gdc ra. Bg phan cat cd hai chi tifit chinh la tSm ke (2) va dao cat (1) lap trfin trdng quay (3). Bd phan va va bam gom cd cac canh gat (7) lap trfin trdng quay thuc hifin vifc va va dua g6c ra dS dugc cat vao bd phan bam, tai dSy cd cac dao bara (6) b6 tri song song vdi nhau dfi th\rc hien bam ngin gdc ra theo nguyfin ly canh gat quay, dao cd dinh.
May cat b5m gdc ra dugc lifin kfit ttudc mdy kdo thdng qua cac Bulong (4). Gdc nghieng ciia tam kfi cd thfi thay ddi nhd xilanh (5). Chieu cao ciia gdc ra sau khi cat cd thfi dugc dieu chinh thdng qua cac bulong (4) va xilanh (5).
Chifiu dai cua cac doan cit phu thudc vao khoang each giira cac dao bam.
CHi CONG NGHIEP NONG THON • SO 11 - 2013
K H O A H O C - CONG N G H E 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 3. 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 4.
Hinh 3. Dao cdt
Hlnh 4. Bgphgn cdt bam gdc rg 1- Bien dgng dao bam; 2 - Dao cit; 3 - Canh gat; 4 - Dao cat co djnh; 5 - 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 ra vira di vao canh sac cua ludi dao vira trugt dgc theo dao, do 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 • A5
qix
-^
Hinh 5. Van tdc tgi diem Mciia dao vdo vdt thdi Ta xet mgt chit difim M chuyfin dgng vdi van tdc CO vach ra hfin mat phing cit mdt q i ^ dao dudng cong sao cho dudng cong cit tit ca cac tia xuat phat tii mgt diem dudi ciing mdt gdc 9.
Lay O lam tam tga do, phuang trinh ciia dudng cong xac dinh tga do cue R va 5 cua mgt difim frfin bfi mat cua dao cat.
Qua hinh ta thay :
Chat difim tai M cd tga do cue: R va 5 s Chat diem tai M[ cd tga do cue: Ri=R +AR, 5 si= 5 s +A 6 s. Tir dd suy ra:
A R - R , - R = M , Q , A 5 s ^ 5 s i - 5 s Nfiu giua phuang phap tuyen n-n ciia dudng cong tai difim M va vec t a 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 6 s, tir dd ta suy ra:
AR-R.A5s.cphay ARyR=A5s.(p TdR
I T - I
dS InR
-•<p<.s,-\) ^
R = fi,/"'"'''' -^ R = R^e"' {Chon S^ =0°) R = RQC'^- . Day la phucmg trinh duong xoan 6c logarit, do thj la ducmg cong bien dang cua dao cat, giai han boi goc khao sat(?^ va tp.
Voi R„=2\5 nun, ^,=120° , ^=25°+30°
ta xac dinh dugc bien dang cua dao bam.
2013 23
KHOA H Q C - C O N G N G H $
bang. May dugc treo phia trudc mdy keo, tmyhn dgng cho bg ph^n cit bam bang ddng co thiiy luc, dieu chinh gdc cit bing xi lanh thiiy lire.
=440 vdng/phiit Kich thit&c vd so lirang cdnh gat Vdi ^^=120° va chifiu dai cit mong mudn L(mm). Ta bd tri tren frdng 3 hang canh ggt each dfiu nhau 120° moi hang bd tri:
N=(H-2L)/L=(450-130)/65=4,9.
Vay sd canh gat tren hang N=5.
Chieu dai canh gat:
Lg - (D - Do)/2 = (650 - 430)/2 =110 mm Thong so dpng hpc
' Van tdc cat:
Ddi vdi ra v^n tdc cat thudng > 15 m/s.
- Sd vdng quay cda frdng:
_ 6Q.F^_ 60.15 . TTD j?r.0,65
- Van tdc tien cua may: Vn,= 0,3-^0,5 m/s - Nang lugng c5t thai va cdng cat thai rifing:
Nang lugng cat thai va dac biet la cdng cat thai rifing la thdng sd quan frgng nhat cua qua trinh cat. Nang lugng cat thai dugc tinh dua frfin co sd xac dinh md men can cat thai M^ va van tdc gdc ciia luoi dao to, cdng suat cat thai dugc tinh:
dF Ma.oi=q—-(\ + ftgT)
at Trong dd:
dF - do tang vi phan ciia difin tich dugc cat thai;
/ - he sd cat trugt;
r - gdc cit trugt, 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 ra frong trudng hgp chat bd r <(pms)-
Ndng suat cda mdy
Nang suat thuan tuy trung binh ciia may:
M-0,36xBxVm=0,36xl,5x0,4= 0,216 ha/h Trong dd:
B - be rdng cit cua may, m;
Vm- vSn tdc lam vific trung binh khi may lam vific trfin ddng, m/s.
3.4. Thiet ke may cat bam
Trfin CO sd nguyen ly, mdt sd thdng sd lira chgn va tinh toan, da thiet kfi mlu may thfi hifn trfin hlnh 6,7,8 va cd dac difim ky thuat ghi d
24 TAP CHi CONG NGHIEP NONG THON • SO 11 - 2013 Hinh 8. Mdy cdt bdm gdc rg treo tnrdc mdy keo
KHOA HQC - C ' ) N G NGHE Thdng sd ky thugt may cdt bdm gdc r
TT 1 2 3 4 5 6 7 g 9 10 11 12
Ten gQi Kich thudc m^y (DxRxC), cm S6 luong Ir6ng quay Chieu cao lam viec cua trong, mm So vong quay ciia tr6ng, v/ph So luong dao cat lap tren trdng Khoang each cdc dao c6 dinh, mm So hang canh gat trSn moi tr6ng So canh gat tr£n m6i hang Duong kinh trong quay, mm Chi6u dai canh ggt, mm Bom thuy luc Mo to thuy lire
Thong s6 75x150x80
2 400 400-600
12 65 3 5 430
110 45 lit/phut 50cm^/v6ng,
7,5 kW
budng bam. Nhin chung, vdi nhiing gdc ra cd gdc nghifing khdng ldn, chat lugng bam tdt, ty lfi phin r?t cd chifiu dai qua ldn chiem ty lfi khdng dang kfi, khdng anh hudng nhifiu tdi cac khau canh tac sau dd. Khi gdc ra nghieng dd cang ldn thi kha nang vo cua cac canh gat cang kem, chifiu dai cac doan cit tang Ifin.
- Tdc do tifin cua may anh hudng dfin kha nang cat va v a cua may. Khi may tifin, tim kfi giii vai trd cua cac miai rfi ddng thdi la cac tam kfi. Khi may tifin cang nhanh, tam ke se Iam cho cac gdc ra bj nghifing dd trudc khi vao viing cat va viing bam. Vdi tdc do tifin ciia may V^ =0,3 -^0,5 m/s may lam vific dn dinh.
3.5. Ket qua thi nghiem tren dong May sau khi chfi tao da Hen hgp vdi may keo banh ldp va tien hanh thi nghiem trfin ddng va cd nhan xet sau:
May lam viec dam bao tdt, khi gdc ra d trang thai dd nga khdng qua ldn (nhd hon 20°) thi ty lfi gdc dugc cat 100%, phan goc dugc bam thanh doan ngan cd chifiu dai nhd han 10 cm chifim ty le cao 60 dfin 90 % tuy theo trang thai ciia cay. Khi gdc ra hi nghieng vdi gdc ldn hon 40" thi chat lugng cat bam cua may giam rd ret.
Tuy nhien trudng hgp nay chi xay ra vdi nhung rudng Ilia gap gid bao trudc khi thu hoach hoac tai nhiing phin liia nam tren vet di chuyfin cua banh xe cua may thu hoach, phan rudng nay chifim mgt ty le nhd.
- Bd phan cat gdm cd tam ke va dao cat di ddng lip tren trdng thuc hien tdt cdng doan cat, dac bifit vdi nhiing gdc ra d frang thai nghifing dd khdng qua ldn (nhd ban 20°). Chifiu cao cat cd thfi thay ddi va difiu chinh linh hoat.
- Sau khi gdc ra da dugc cat, cac canh gat lip tren hai frdng quay nguge chifiu nhau cd nhiem vu v o va dua phan frfin cua gdc ra vao TAP CHf CONG NGHIEP NONG THON - SO 11 •
Hinh 9. Mdy cdt bdm gdc rg lam viec tren
Hlnh 10. Xdc dinh kit qud khdo nghidm
2013 25
K H O A H O C - C O N G N G H f
Hinh 11. Hmh dnh cdy rg sau khi may ldm viec IV. KET LUAN
May cit bam gdc ra thuc hien ddng thdi hai nhiem vu cit va lam ngin gdc ra thanh nhifiu doan ngan tao thuan lgi cho cac khau canh tac sau do dfi diet cac mam bfinh li trong cac gdc ra va Ilia tai sinh. Mlu may cat bam gdc ra hai frdng quay nhu da gidi thifiu da dugc chfi tao va khao nghiem cho thay cac ket qua rat tdt. Theo nguyen ly frfin cd thfi cai tien may nhd ggn hem dfi lien hgp trfin may keo nhd. Mau may la ca sd cho vific nghifin cim phat trifin lifin hgp may cat bam gdc ra, lam dat toi thifiu va gieo dau tuong sau nay.
TAI LIEU THAM KHAO 1. Nguyen VSn Chifin (2012), " Bdo cdo kk qua thuc hien kk ho^ich 6 thang dau n5m 2012 nganh Nong nghiep va Phdt trifin N6ng thon".
2. Nguyen VSn Hyu (2000), nghien ctru mpt so thong sd ca ban cua bo phan dap lua d^c true cH nho loai rang, ban, Luan an tien sT kJ thuat.
3. Tran Minh Vugng (2003), May phuc vu ch3n nuoi, Nha xuat ban gido due.
4. Le Minh Lu, Nguyen Xuan Thiet, Nguyin V3n Tam (2011), "Mgt s6 dS xuSt cdi tien bg phan dap trong may thu hoach liia theo hiring d$p tich h^t d6ng th&i bam rom dl khai th^c hieu qua rom sau thu hoach a Viet Nam", Tap chi khoa hgc vd phdt triln, (so 4).
5. Dau The Nhu (2010), Nghifin ciiu c6ng nghe va thifit bi thu gom, bao quan va chl biln rom ra sir dyng c6 hifiu qua, Bdo cdo chuyfin dl nghifin ciiu thiit kl chl tao may bdm rom vd goc ra.
Ngay nhan bai: 8/11/2013 Ngay phan bi^n: 10/12/2013
Nguo"! phan bi$n: TS. Doan Xuan Thin, Hgi ca khi nong nghiep Viet Nam.
KHAO SAT THtrC NGHIEM...
(Tiip trang 20) Nhu vay, kfit quit lya chgn toi uu vdi ba thdng sd nhu sau [2]: E)0 i m : 11,04%, Ty lfi nhifin lieu tieu thu: 1,50kg/h, Toe dg chay: 0,29m/h.
IV. KET LUAN
1. He thdng khi hda tinh theo me nguge chieu d6i vdi kifiu Id sii d\mg khdng khi ddi luu tu nhifin vdi cdng suat nhifit nam trong khoang 6,0-6,5 kW da dugc khao nghifim vdi nguyen Ueu tir phu pham go/dam go. San phim khi tdng hgp
"Syngas" dugc sinh ra va sau khi ddt chay san phim khi tdng hgp nay cho thay vdi nggn Iua mau vang nhat va xanh, dieu do cho thiy chit lugng khi "Syngas" smh ra tdt, it tro bui. Ld boat ddng dn dinh ddi, difiu dd cd ngMa qua tihih smh khi Gas lifin tuc, nguyen ly Id lua chgn thifit kfi diing, dat yeu ciu, phd hgp vdi kifiu Id khi hda ttnh theo me diing khdng khi ddi luu tu nhien. He sd chuyfin ddi nang lugng dat dugc tir nghifin ciiu thuc nghifim 85,57%.
2. Kfit qua quy ho^ch hda thuc nghiem cho ta he sd chuyfin ddi nang lugng dgt dugc 86% tuong ling vdi cac thdng sd tdi uu dat dugc: Do am nguyfin lieu (11,04%); Ti lg nhifin Ueu tieu thu (l,50kg/h); Tdc do chay (0,29m/h).
TAI LI$U THAM KHAO [1]. Nguyen, Dinh Tung (2009): Theoretische und experimentelle Untersuchungen zur energetischen Nutzung landwirtschaftlicher AbfSUe aus Vietnam, Dissertation an der Universitat Rostock, Deutschland.
[2]. Nguyin Dinh Tiing, Nguyfin Dinh Quy va cs.
(2013): Nghifin cihi thilt ke chl tao mgt s6 mlu (Prototype) 16 dot h6a khf c& nh6 sii dung cdc phu phim nong nghidp d?ng t\r nhifin, Bdo cdo nghifm thu hgi dong CO so, De tdi nghifin ciiu c^p B$ 2013, Eg Cong Thuong.
[31. UNDP (2005). Biomas Energy for Heating and Hot Water Supply in Belarus. Best Practice Guidelines, Part A: Biomass Combustion.
[4]. DECC and NNFCC (2009). Review of Technologies for Gasification of Biomass and Wastes.
[5]. Martin Kaltschmitt, Hans Hartmann, Hemiann Hofbauer (2011): Energie aus Biomasse, Springer Verlag.
Ngay nh^n bai: 12/12/2013 Ngay phan bifn: 28/12/2013
Ngiroi phan bi|n: GS.TSKH. P h ^ Van Lang, Aoi CO khi nong nghi?p Vi|t Nam.
TAP CHi CONG NGHIEP NONG THON - SO 11 - 2013
