Tap chi Khoa hgc va Phat triln 2009: Tap 7, sd 5: 678 - 686 TRU'ONG BAI HOC NONG NGHIEP HA NQI XAY DUYJG MACH DIEU KHIEN TRUYEN DONG THUY LUC DA DIEM TREN CAC MAY NONG LAM NGHIEP TlT HANH Designed Multi-Point Hydraulic Transmission Controlling Circuit on Self-Propelled Forestry - Agricultural Machines Dirong Trung Hieu', Biii Hai Trieu^ 'Tru&ng Cao ddng nghe Ca nong nghiep - Tam Hap Binh Xuyen, VTnh Phiic ^ Tru&ng Dgi hoc Nong nghiep Hd Noi - Trdu Quy, Gia Ldm, Hd Noi Dja chi email tac gia lien lac: hieuvcam8@ginail.com '( " ' ' TOMTAT Hien nay, cac lien hop may san xult o* Viet Nam tdn tai mgt s6 nhu'O'c diem v§ khong gian, kich thu'O'C, trgng lu'O'ng nen chu'a phat huy du'O'c hieu qua tdi da N h i m khic phuc cac nhu'O'c diem tren, nghien cii'u tiln hanh phan tich va xay du>ng mach dilu khiin truyin dong thuy lire da diim d l lam CO so' cho viec nghien ciru, thilt k l cac he thdng mach dilu khiin va truyin dgng thuy lire da diim tren cac may nong lam nghiep tir hanh ap dung vao thirc te lirong lai TU" khoa: Mach d i l u khien, lien ho'p may, t r u y i n dong thuy lire SUMMARY Multihead machines have been invented and applied in Vietnam However, those machines often use mechanical transmission system and only a few of them use one-point hydraulic transmission system Mechanical transmission has some drawbacks of space, size, weight, etc., leading to the inefficiency of those machines As a result, the practical demands have required us to research, analyze and make multi-point hydraulic transmission controlling circuit This research will be the foundation for the next research and invention of controlling circuits and multi-point hydraulic transmission of self-operated machines that can be practically applied in agriculture and forest sectors in the future Key words: Controlling circuit, multihead machines, hydraulic transmission D A T V A R D E Hien nay, viee thiet ke va phat trien eac loai may philc hdp tu hanh dang dien het siie sdi ddng linh viic cd hoa ndng lam nghiep d nUde ta Xu hUdng thiet ke ehu ye'u la bd' tri cac bd phan lam viee, dan ddng cho cac bd phan lam viee ehii ddng tren mdt may keo van nang ed nhd hoac la thiet ke' eae may phiic hdp chuyen biet cho eac cdng viee ndng lam nghiep nhU gieo trdng, cham sdc va 678 u u v thu hoach Tren da sd' cae m l u may da dUde cdng bd': Cae may lam da't, may thu hoach viec truyen ddng trich edng suat duge thiie hien bang cd hgc nhU truyen ddng xich, truyen ddng dai, truyen ddng eac dang hoac truyen ddng banh rang NhUde diem eua truyen dgng ed hge la viec thay ddi ty sd truyen vd ca'p chi cd the thiic hien khoang gidi han va yeu clu mdt khong gian lap dat cd' Xay dung mach dieu l