Structure Analysis and Optimization for Compacting System of Asphalt Paver

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1 Send Orders for Reprns o reprns@benhamscence.ae 86 The Open Mechancal Engneerng Journal, 05, 9, 86-9 Open Access Srucure Analyss and Opmzaon for Compacng Sysem of Asphal Paver Sun Jan * Mechancal and Elecronc Deparmen, Xuzhou Insue of Technology, Jangsu Key Laboraory of Large Engneerng Equpmen Deecon and Conrol, Xuzhou, Chna Absrac: Compound moon of double-amper mechansm causes an mpac force on he frame of flaron-box, whch affecs he qualy of he load when he asphal paver s runnng. Dfferen from he prevous smplfed model, n hs paper, he double-amper mechansm wh wo parallel slder-cranks s consdered. Accordng o he analyss of he srucure and prncple of he mechansm, and consderng he sze and mass dsrbuon of each componen, he nera force balance opmzaon for he double vbrang mechansm s calculaed. Accordng o he resuls of opmzaon, he vbraon expermens were carred ou on real screed. The expermenal resuls show ha, he harmful neral force produced by he dual ampng mechansm has been sgnfcanly reduced, and he sably of vbraon can be effecvely mproved when screed pavng. The research could provde relable heorecal mehod and bass for desgn, manufacurng and use of asphal concree paver. Keywords: Asphal paver, opmzaon, srucure analyss, amper mechansm.. INTRODUCTION Compacng sysem s he key devce for asphal concree paver. I acheves modelng, levelng and compacon of pavng roads []. The screed wh double-amper mechansm has been wdely appled n he marke due o he characerscs of good levelng hgh densy and hgh operang effcency. The double-amper mechansm n he fron of he screed s drven by he roaon of he vbrang beams, and s roaonal frequency s commonly beween 0 ~ 5 Hz. The rgh choce of he srucure and dynamcs parameers of compacng sysem relaed o he paver cause o relably. The amper and he eccenrc vbraon mechansm of screed drecly affec he pavng flaness and compacness. Expermenal sudes have found ha he amperng wll produce harmful mpac o screed, whch leads o uneven pavng of roads and uneven pre-compacon. In some early researches, he movemen of he amper mechansm s smplfed as smple harmonc vbraon and ddn ake he vbraon of he vbrang beams no accoun []. Few sudes [3] have nvesgaed he heorecal calculaon based on he mehod of complex vecor. The process of hs mehod s rval and only he movemen parameers of he amper mechansm can be calculaed. In hs paper, he srucure and workng prncple of amper mechansm were analyzed, and hen he double-amper wh wo parallel slder-cranks mechansm are analyzed, consderng he sze and mass dsrbuon of each componen. The nera force balance analyss was carred ou on he double amper mechansm, opmzng s srucure parameers, and reducng s mpac on he screed vbraon.. STRUCTURE AND WORK PRINCIPLE OF THE TAMPER MECHANISM The srucure of double-amper mechansm of screed s shown n Fg. (), he man vbrang pars nclude: he eccenrc shaf, man vbrang beam, auxlary vbrang beam, man eccenrc sleeve and auxlary eccenrc sleeve [4]. The nal compacon of he pavng mxure s realzed by up and down movemen of he vbraon beam whch s caused by he roaon of he eccenrc shaf. The man and auxlary vbrang beams are consdered as he slab and grder srucure. The op of he beams are rgd, and he beams are hanged on he eccenrc shaf. f, X/5 Fg. (). Srucure ype of double-amper mechansm. The power of amper mechansm s suppled by hydraulc moor, speed can be adjused by a roary flow speed conrol 05 Benham Open

2 Srucure Analyss and Opmzaon for Compacng Sysem of Asphal Paver The Open Mechancal Engneerng Journal, 05, Volume 9 87 valve and he workng speed s ranges from 0 ~ 500 r/mn. Amplude s vared by adjusng roaon angle of he man and auxlary eccenrc sleeve [5]. The eccenrc shaf s a power ransmsson par of amper mechansm and he man mechansm of amplude generaon, whch s shown n Fg. (). knds of combnaons. Accordng o he srucure prncple of amper mechansm, dfferen amplude combnaons of man and auxlary vbrang beam are shown n Fg. (4). Fg. (). Srucure of eccenrc shaf. In Fg. (), O-O s he roary cener lne of eccenrc shaf, O -O s he eccenrc cener lne of man vbraon, O - O s he eccenrc cener of auxlary vbraon. When he eccenrc shaf roaes abou he roaon cener lne O-O, he O -O and O -O eccenrc cener lnes do he eccenrc movemen around O-O respecvely, he eccenrc moon s he movemen source of compose moon for he eccenrc shaf and eccenrc sleeve. The man and auxlary eccenrc sleeve are also eccenrc pars. The man eccenrc sleeve s nsalled on he eccenrc shaf O -O and s used for he amplude adjusmen of he vbraor s man vbrang beam. The auxlary eccenrc sleeve s nsalled on he eccenrc shaf O -O and Used for amplude adjusmen of vbraor s auxlary vbrang beam. The srucure of man and auxlary eccenrc sleeve are smlar, and he schemac dagram of he eccenrc sleeve s shown n Fg. (3). Fg. (4). Amplude combnaon of he double ampers. In Fg. (4), e d s he man vbraor eccenrcy, e d s he auxlary vbraor eccenrcy, e dz s he he eccenrc quany of he man vbrang shaf neck, e d s he eccenrc quany of man eccenrc sleeve, e dz s he eccenrc quany of he auxlary vbrang shaf neck, e d s he eccenrc quany of auxlary eccenrc sleeve. Accordng o Fg. (4), he eccenrcy of man vbrang mechansm can be expressed as follows.! e d = e dz + e d e dz e d cosα d! () he eccenrcy of auxlary vbrang mechansm s e d = e dz + e d e dz e d cosα d () Accordng o he rgonomerc relaonshps n Fg. (3), he geomerc equaons can be obaned as follow. Fg. (3). Srucure of eccenrc sleeve. In Fg. (3), O s -O s s he roary cener lne of eccenrc sleeve, O e -O e s he eccenrc cener lne of eccenrc sleeve, e d s he he eccenrc quany. Amplude change s realzed hrough adjusng roaon angle of he sleeve ha s arranged on he eccenrc shaf. There are some markers n he surroundng of he eccenrc sleeve. When roang he eccenrc sleeve o make he markers algn wh he scrbed lne on he connecng flange, whch can oban he requred amplude. The varey of dfferen combnaons of ampludes can be obaned by adjusng he eccenrcy of he eccenrc shaf and eccenrc sleeve, and also dfferen phase dfferences can be acheved beween he he man and auxlary vbrang beams. The amplude of double-amper mechansm has a varey of combnaons [6]. A ceran company's screed vbraor mechansm s used for analyss n he followng example. The man vbraon amplude of he screed s 3, 5, 7 and 9 mm, and he auxlary vbrang amplude s 0, 3, 6, 9 and mm. The adjusmen mehod of he amplude has many cosφ d = e d + e dz e d e d e dz cosφ d = e d + e dz e d e d e dz The relaonshp beween amplude and he correspondng phase angle of man and auxlary vbrang beam s as follows: φ = 80 +φ d φ d e =80 + cos d + e dz e d e d e dz e!!!!!!!"cos d + e dz e d e! d e dz By equaon 4, we can ge ha phase Angle beween he man and he auxlary vbrang beam deermned by he amplud e of he man and he auxlary vbrang beam. Gven a se of amplude values, we wll deermne a fxed Phase Angle value. Accordng o he man and auxlary vbrang sroke adjused workng sroke, here are 0 knds (3) (4)

3 88 The Open Mechancal Engneerng Journal, 05, Volume 9 Sun Jan Table. Phase beween he man and auxlary amper. SN Sroke/mm Phase Angle/( ) SN Sroke/mm Phase Angle/( ) 3, , , , , , , , , , , , , , , , , , , , 80 of sae. The calculaed phase angle correspondng o each sae beween man and auxlary vbrang beam s shown n Table. 3. STRUCTURE OPTIMIZATION Knemacs essence of amper mechansm can be denfed as wo ses of offse slder-crank mechansm n parallel. When operang, he eccenrc shaf roaon produces a large neral mpac force whch wll cause he vbraon of he screed [7]. The man role of he double amper mechansm s prelmnary rammng maeral, so s nfluence on he screed would be elmnaed. The man and auxlary vbrang beam s ask s o parally offse he neral force. However, he curren desgn of he amper mechansm s only a smple maon of mpored equpmen and here s no analyss of s calculaon. So he desgn of he amper beam somemes ncreases he nera force of mechansm, whch wll have grea nfluence on he pavng qualy of he screed. For mechancal componens wh recprocang moon or general plane moon, he balance problem s generally more complex, ofen only par of he balance of nera force s obaned. In hs paper, he mehod of planar mechansm balance s adoped o reduce he vbraon of he double vbrang mechansm [8]. The calculaon model of he srucure of he double amper mechansm s shown n Fg. (5). where G d ~G d4 ndcae each cenrod of he four rgd body ha are man and auxlary vbrang beam, man and auxlary eccenrc sleeve, θ d s he nal phase angle of he man vbraon, θ d s he nal phase angle of he auxlary vbraor, θ d3 s he angle beween he cenrod symmery plane and he vercal plane of man vbrang beam, θ d4 s he angle beween he cenrod symmery plane and he vercal plane of auxlary vbrang beam, Ф s he phase dfference beween man vbrang beam and auxlary vbrang beam, a s he dsance from he cenrod o eccenrc cener of man vbrang beam, a s he dsance from he cenrod o eccenrc cener of auxlary vbrang beam, a 3 s he dsance from symmery plane of cenrod cener o eccenrc cener of man vbrang beam, a 4 s he dsance from symmery plane of cenrod cener o eccenrc cener of Fg. (5). Calculaon model of double-amper mechansm. auxlary vbrang beam, e d s he dsance from symmery plane of cenrod cener o roaon cener of man vbrang beam, e d s he dsance from symmery plane of cenrod cener o roaon cener of auxlary vbrang beam, l s he hegh of he man vbrang beam, l s he hegh of he auxlary vbrang beam. Assume ha he eccenrc shaf s n unform moon around he axs O wh angular velocy. OE s he crank radus of man vbraon, OE = r d, EB s he connecng rod, EB = l d = l + a 3, ε d s he man vbraor eccenrcy, ε d = e d r d. Then he end dsplacemen of man vbraon beam can be expressed as follows: y d = l d r d λ d e d + λ r d 4 ( cosω ) + d + λ d ( ) λ de d (5) where λ d s he crank connecng rod rao of man vbraon, λ d = r d l d.

4 Srucure Analyss and Opmzaon for Compacng Sysem of Asphal Paver The Open Mechancal Engneerng Journal, 05, Volume 9 89 The man vbrang beam end speed can be expressed as: y d = r d + λ d ε d + λ d snω d (6) The man vbrang beam end acceleraon can be expressed as: y d = r d ω d ( λ d ε d + λ d ) (7) OF s he crank radus of auxlary vbraon, OF = r d, FC s he connecng rod, FC = l d = l + a 4, ε d s he man vbraor eccenrcy, ε d = e d r d. Then he end dsplacemen of auxlary vbraon beam can be expressed as follows: y d = l d r d λ d e d + λ dr 4 ( ) + ( ) λ d + λ d (8) e d The auxlary vbrang beam end speed s expressed as: y d = r d + λ d ε d + λ d snω d (9) The auxlary vbrang beam end speed s expressed as: y d = r d ω d ( λ d ε d + λ d ) (0) The man and auxlary vbrang eccenrc sleeve roae wh he eccenrc shaf, and only produce roary nera forces, wh mass m d and m d4, respecvely. The man and auxlary vbrang beam make plane moon, and produce roary nera force and recprocang nera force, wh mass m d and m d3, respecvely. The forces of man and auxlary vbrang beam can decompose no he alernave forces, m E and m F, concenraed n he man and auxlary eccenrc sleeve cener, o do roary moon, and he alernave forces m B and m C, concenraed n he man and auxlary vbrang end, o cause recprocang movemen. As shown n Fg. (4), he cenrod of man and auxlary vbrang beam s no conneced o he cenrod and he man and auxlary vbraon connecng rod ends. The vecor calculaon mehod s used o deermne he value of alernave force. The alernave cenrod of he member concdes wh he cenrod poson of he orgnal componens. and r B represens he vecor of he roaonal cener of man vbrang beam E and he end poron of he man vbrang lnk D, respecvely, hen he alernave qualy of man vbrang m d4 can be expressed as m d + m B m d r Gd + m B r B () Accordng o he rgonomerc relaonshps n Fg. (4), he geomerc equaons can be obaned as follow. r Gd = + L EGd L EGd = ( p + q ) L EB where L EB can be expressed as L EB = + r B Then, r Gd can be expressed as r Gd = ( + p + q ) + ( p + q ) r B () Eq. s subsued no Eq. m d ( + p + q ) + m d ( p + q ) r B + m B r B (3) Then, he alernave qualy of man vbrang s shown n Eq.4. m E = l + p EB m d m B = p m d (4) Replace no he roaon cener of mass of man vbraon beam and eccenrc sleeve and can be vewed as he roang mass of man vbrang mechansm, whch s shown n Eq.5 m S + m d = m d + + p m d m d (5) The roang mass of man vbraon mechansm produces cenrfugal force n he ouward drecon along he crank, whch s expressed as F S = m S (6) Replace no he end qualy of man vbraon beam wll produce recprocang neral force whch moves along he vercal drecon, as formulaed n Eq.7. F B = m B r d ( λ d ε d (7) +λ d ) The same as he man vbrang mechansm, he alernave qualy of he auxlary vbrang mechansm can be expressed as Eq.8 m F = l + p FC l FC l FC m d3 m C = p l FC l FC m d3 (8) Replace no he roaon cener qualy of auxlary vbraon beam and eccenrc sleeve and can be vewed as

5 90 The Open Mechancal Engneerng Journal, 05, Volume 9 Sun Jan he roang mass of auxlary vbrang mechansm, as formulaed n n Eq.9. m S = m F + m d4 = m d4 + l + p FC m d3 m d3 l FC l FC r (9) F The roang mass of auxlary vbraon mechansm produces cenrfugal force n he ouward drecon along he crank, whch s expressed as F S = m S (0) Replace no he end qualy of auxlary vbraon beam wll produce recprocang nera force whch moves along he vercal drecon, as formulaed n Eq.. F C = m C r d ( +λ d ) λ d ε d () Because he man and auxlary vbrang beam are arranged a 80 degrees o each oher, and he srucure arrangemen s bascally fxed, so can be a reasonable assumpon, based on he locaon and mass parameers of he man and auxlary vbrang beam, o make he resulan forces of he roang neral forces and recprocang neral forces reduced and o reduce he nfluence of double vbraon mechansm on he ronng plae vbraon [9]. The purpose of balance of mechansm s o make he cenrfugal force, generaed by roaon of he man and auxlary vbrang beam be equal and oppose n drecon and cancellng he effecs of each oher ou as formulaed by eq.. F S = F S F B = F C () Accordng o he above requremens, akng he amplude of he man vbrang beam as 5 mm, he amplude values of he auxlary vbrang beam s 6 mm. Subsued no double vbraor mechansm parameers, he srucure and qualy parameers of man and auxlary vbrang beam are obaned by calculaon whch are abulaed n Table. Among hese, λ d s very small, so s gnored. Table. Phase beween he man and auxlary amper. Man Vbrang Beam Auxlary Vbrang Beam 4. EXPERIMENT VERIFICATION r d/mm.5 m d/kg 90 p /mm 33.9 q /mm.7 r d/mm 3 m d3/kg 63. P /mm 9.84 q /mm 3.03 To verfy he calculaon resuls, he real es s carred ou on he screed. Durng he expermen, he screed frame s suppored by he res, vbraon beam vacan, acceleraon sensor selecvely arranged on each measurng pon of he framework. Accordng o he above opmzaon resuls, qualy parameers for each secon of he double-amper mechansm of he screed are adjused, we do he analyss of he sysem a 0 Hz and 0 Hz vbraon frequences. Then, he resuls before and afer adjusmen are shown n Fgs. (7, 8). The L4 ~ R4 represens each screed for segmen arranged from lef o rgh Fg. (6). From he comparson of he resuls of double-amper mechansm before and afer parameers adjusmen, we can conclude ha under dfferen vbraon frequences, he effecve value of vbraon acceleraon of secon screed cenrod decreases percepbly afer screed dual ampng mechansm were mproved, whch s a 0 Hz. The mean effecve value of he acceleraon s reduced by 43.48%, a 0 Hz, and he mean effecve value of he acceleraon s reduced by 43.70%. Under dfferen frequences, he vbraon sandard devaon of he ronng plae frame, afer mprovemen, was reduced, so he whole vbraon unformy s mproved. CONCLUSION In hs paper, hrough he analyss of he srucure of he double ampng mechansm, he relaonshp beween he amplude and he phase angle of man and auxlary vbrang beam s obaned. The double-amper mechansm wh wo parallel slder-cranks mechansm s consdered for analyss, and he heorecal calculaon model of mechansm s esablshed. Then, he nera force balance analyss s Fg. (6). Vbraon es for screed.

6 Srucure Analyss and Opmzaon for Compacng Sysem of Asphal Paver The Open Mechancal Engneerng Journal, 05, Volume 9 9 Fg. (7). 0 Hz, Inera force comparson of mechansm. Fg. (8). 0 Hz, Inera force comparson of mechansm. carred ou on he double amper mechansm, and he srucure parameers are opmzed, whch makes he acceleraon RMS of he screed reduce by abou 43%, and effecvely reduce he nfluence of vbrang mechansm on ron ables. The research of hs paper could provde a reference for he desgn of double-amper mechansm for asphal paver and he adjusmen of consrucon parameers. CONFLICT OF INTEREST The auhor confrms ha hs arcle conen has no conflc of neres. ACKNOWLEDGEMENTS Declared none. REFERENCES [] L. Gang, T. Jnyue, X. Zhongyu, and X. Langquan, "Smulaon of dynamc characer of compacng mechansm of paver", J. Agrcul. Mach., vol. 36, no., pp , 005. [] Q. Xu, Knemac analyss of amper mechansm for paver, Road Mach. Consruc. Mechanza., vol. 3, no. 3, pp. 5-9, 006. [3] G. Zhao, Analyss on dynamc characersc of ronng mechansm of asphal concree paver, Road Mach. Consruc. Mechanza., vol. 6, pp , 009. [4] Z. j, Explanaon for alphabec markng prncple on he eccenrc sleeve n dual ampng mechansm of he screed, Consruc. Mach. Equp., vol. 38, no. 8, pp. -3, 007. [5] F. Zhong-xu, Z. Ln-bo, W. Xan-xue, Dynamc smulaon and paramerc selecon for ampng mechansm of pavng machnes, Chnese J. Consruc. Mach., vol.7, no., pp.6-30, 009. [6] Z. Xnrong, Z. Guopu, S. Zuwang, Dynamcs analyss of screedng un for asphal paver, J. X an Hghway Unv., vol., pp , 00. [7] Z. Shwe, G. Zhonghua, Z. Jnglang, Mahemacal model and mehod of dynamc balance for wo knds of screw roors, In. J. Adv. Compu. Technol., vol. 6, no. 4, pp [8] W. Jun, Z. Sheng-dun, S. Hu-shan, A mehod o calculae and counerbalance he nera force of slder-crank mechansms n hgh-speed presses, Academc J. X an Jaoong Unv., vol., no.3, pp [9] Q. L-L, C. Xao-hu, Balance analyss of recprocang nera force based on mul-body sysem smulaon, Adv. Ma. Res., vol , pp , 0. Receved: January 8, 05 Revsed: January 5, 05 Acceped: January 6, 05 Sun Jan; Lcensee Benham Open. Ths s an open access arcle lcensed under he erms of he Creave Commons Arbuon Non-Commercal Lcense (hp://creavecommons.org/lcenses/by-nc/3.0/) whch perms unresrced, non-commercal use, dsrbuon and reproducon n any medum, provded he work s properly ced.