Title (srp)

Analiza radnih karakteristika i unutrašnjih tokova snage složenih cikloprenosnika

Author

Mačkić, Tihomir, 1973-

Contributor

Marjanović, Nenad, 1961-
Ivanović, Lozica, 1964-
Stojanović, Blaža, 1974-
Rackov, Milan, 1976-
Tica, Milan, 1974-
Matejić, Miloš, 1988-

Description (srp)

U ovom radu predstavljen je matematički model koji omogućuje procenuosnovnog stepena iskorišćenja za dve varijante jednostepenog cikloprenosnika,od kojih je jedna sasvim nova koncepcija sa stepenastim ciklozupčanicima. Radijednostavnije analize, klasična varijanta je nazvana „VD“, dok je varijanta sastepenastim ciklozupčanicima nazvana „2V“. Objašnjeni su uslovi pri kojimamože nastupiti samokočivost prenosnika. Prikazan je način određivanja tokarelativne snage i izrazi za računanje stepena iskorišćenja svih radnih režima.Pokazano je da vratilo venca, za tip „VD“ i vratilo venca 1 (venca sa manjimbrojem valjčića) za tip „2V“, predstavljaju zbirna vratila, a da su ostala dvavratila diferencijalna. Izvedeni su izrazi za intenzitete relativnih brzinaspregnutih profila, u tački dodira, i intenzitete brzine klizanja i zbirnebrzine kotrljanja. Definisani su obrtni momenti i sile koje deluju na elementeprostog cikloprenosnika i izvedeni izrazi za određivanje intenziteta sila.Sagledan je uticaj zazora i deformacija na veličinu i promenu kontaktnih sila.Predstavljen je teorijski model koji određuje gubitke usled postojanjarelativne snage, kako za ograničene, tako i za diferencijalne jednostepenecikloprenosnike. Izrađen je algoritam i program, koji se bazira na predstavljenom modelu i izrazima za određivanje geometrijskih, kinematičkih, statičkih itriboloških veličina i urađena je analiza uticaja ovih veličina na osnovnistepen iskorišćenja. Uočene su mnogo bolje karakteristike, ako cikloprenosnici koriste igličaste ležajeve kao valjčiće na vencima.Prikazani su mogući režimi toka unutrašnje snage diferencijalnogcikloprenosnika i zavisnost ovih tokova od položaja zbirnog vratila i vratilaukupne snage. Uočeno je postojanje tzv. „beskorisne snage“, koja predstavlja manjuparcijalnu snagu, koja je usmerena suprotno od efektivne snage. Definisane sustrukture dvostepenih cikloprenosnika i način označavanja strukturnihslogova i vratila, uz korišćenje Volfovog simbola. Detaljno su sagledanimogući tokovi snage kroz ograničeni dvostepeni cikloprenosnik i objašnjen jeuslov pojave podele i cirkulacije unutrašnje snage. Izdvojeno je ukupno 8 šemagde dolazi do podele snage i 13 šema u kojima se javlja cirkulacija snage.Definisana je metodologija za određivanje radnih karakteristika,gubitaka i unutrašnjih tokova snage složenih cikloprenosnika. Kreiran jeprogram koji omogućava izbor varijante i vanjskog toka snage, unos ulaznihparametara, određivanje toka relativne snage kroz strukturne slogove i procenuvrednosti stepena iskorišćenja cikloprenosnika. Izvršena je analiza 21varijante ograničenog dvostepenog cikloprenosnika. Izrađeni su fizičkimodeli cikloprenosnika i eksperimentalno provereni, kako bi se potvrdilimatematički modeli i verifikovala definisana metodologija. Konstatovana jeveoma dobra korelacija između teorijskih i eksperimentalnih rezultata, pričemu faktor srednjih gubitaka ne prelazi 3%, za sva merenja.

Description (srp)

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Description (eng)

In this paper, a mathematical model is presented that enables the assessment ofthe basic efficiency for two types of simple cycloid drive train, one of which is acompletely new concept with stepped cycloid gears. To simplify the analysis, theclassical type is named "VD", while the type with stepped cycloid gears is named "2V".The conditions under which self-locking can occur are explained. The method ofdetermining the internal power flow and expressions for calculating the efficiency of alloperating modes are presented. It is shown that the central gear shaft, for the type "VD"and the central gear shaft 1 (the central gear with a smaller number of rollers) for the"2V" type, are summation shaft, and the other two are differential shafts. Expressionswere derived for the intensities of the relative speeds at the point of contact of thecoupled profiles and the intensities of the sliding speed and the total rolling speed.Torques and forces acting on the elements of a simple cycloid drive train are defined andexpressions for determining the intensity of forces are derived. The influence ofclearances and deformations on the size and change of contact forces is shown.A theoretical model is presented that determines losses due to the existence ofrolling power, both for simple and differential cycloid drive trains. An algorithm andprogram based on the presented model and expressions for determining geometric,kinematic, static and tribological parameters were developed and the influence of theseparameters on the basic efficiency was analyzed. Much better characteristics have beenobserved if the cycloid drive trains use needle bearings as rollers on the central gears.The possible modes of the internal power flow of the differential cycloid drivetrain and the dependence of these flows on the position of the summation shaft and thetotal power shaft are shown. It was observed the existence of the so-called "futilepower", which represents a smaller partial power, which is directed opposite to theeffective power. The structures of bicoupled cycloid transmmisions and the way ofdenotation of a simple cycloid drive train and shafts are defined, using the Wolf symbol.Possible internal power flows through the constrained bicoupled cycloid drive trains arereviewed in detail and the condition for the appearance of division and circulation ofinternal power flow is explained. A total of 8 schemes where power division occures and13 schemes in which power circulation occurs were singled out.A methodology for determining the operating characteristics, losses and internalpower flows of compound cycloid transmissions is defined. A program was created thatenables selection of the variant and external power flow, entry of input parameters,determination of the flow of rolling power through the structural cycloid drives andevaluation of the efficiency of the bicoupled cycloid drive train. An analysis of 21variants of the constrained bicoupled cycloid drive trainс was performed. Physicalmodels of bicoupled cycloid drive trains were created and experimentally verified, inorder to confirm the mathematical models and verify the defined methodology. A verygood correlation between theoretical and experimental results was established, with theaverage loss factor not exceeding 3% for all measurements.

Object languages

Serbian

Date

2023

Rights

Creative Commons License
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CC BY 3.0 AT - Creative Commons Attribution 3.0 Austria License.

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Identifiers