{"id":9800,"date":"2014-11-30T19:36:47","date_gmt":"2014-11-30T17:36:47","guid":{"rendered":"http:\/\/mixmotor.eu\/?p=9800"},"modified":"2014-11-30T19:36:47","modified_gmt":"2014-11-30T17:36:47","slug":"vackovy-hriadel-minulost-sucasnost-buducnost-cast-i","status":"publish","type":"post","link":"https:\/\/mixmotor.eu\/de\/9800\/vackovy-hriadel-minulost-sucasnost-buducnost-cast-i","title":{"rendered":"Va\u010dkov\u00fd hriade\u013e. Minulos\u0165, s\u00fa\u010dasnos\u0165, bud\u00facnos\u0165 – \u010das\u0165 I."},"content":{"rendered":"

Va\u010dkov\u00e9 hriadele s\u00fa s\u00fa\u010das\u0165ou stroj\u00e1rstva po st\u00e1ro\u010dia. Ich po\u010diatky siahaj\u00fa a\u017e do 3. storo\u010dia pred Kristom. V\u00a0Helenistickom obdob\u00ed boli pou\u017eit\u00e9 u vodou hnan\u00fdch automatov. Od t\u00fdchto \u010dias pre\u0161li dlh\u00fa cestu a\u00a0stali sa s\u00fa\u010das\u0165ou mnoh\u00fdch zariaden\u00ed.<\/p>\n

Pre na\u0161ich \u010ditate\u013eov bud\u00fa pravdepodobne podstatnej\u0161ie tie, pou\u017e\u00edvan\u00e9 v\u00a0spa\u013eovac\u00edch motoroch. Sl\u00fa\u017eia k\u00a0prenosu rota\u010dn\u00e9ho pohybu k\u013eukov\u00e9ho hriade\u013ea na vratn\u00fd transla\u010dn\u00fd pohyb ventilov, ktor\u00e9 zabezpe\u010duj\u00fa v\u00fdmenu obsahu pracovn\u00e9ho priestoru valca.<\/p>\n

Na \u010do sl\u00fa\u017ei va\u010dkov\u00fd hriade\u013e? –\u00a0N\u00e1h\u013ead k\u00a0z\u00e1kladom<\/h3>\n

Va\u010dkov\u00fd hriade\u013e rotuje v bloku motora a zvy\u010dajne je poh\u00e1\u0148an\u00fd rozvodom od k\u013eukov\u00e9ho hriade\u013ea. S\u00fa na \u0148om umiestnen\u00e9 jednotliv\u00e9 va\u010dky, ktor\u00e9 zabezpe\u010duj\u00fa pohyb rozvodov\u00e9ho mechanizmu. Pohyb va\u010dky sa pren\u00e1\u0161a na zdv\u00edhadlo trec\u00edm alebo valiv\u00fdm kontaktom. Po\u010das ot\u00e1\u010dania jednotliv\u00e9 va\u010dky otv\u00e1raj\u00fa a zatv\u00e1raj\u00fa sacie a v\u00fdfukov\u00e9 ventily v\u00a0z\u00e1vislosti na polohe piesta, ktor\u00e1 umo\u017e\u0148uje nas\u00e1vanie a v\u00fdfuk zmesi.<\/p>\n

Ve\u013emi d\u00f4le\u017eit\u00fd je profil v\u00fdbe\u017eku va\u010dky. Tvar profilu v\u00fdbe\u017eku mus\u00ed zabezpe\u010di\u0165 najvhodnej\u0161ie plnenie valca, teda zdvih ventilu mus\u00ed by\u0165 \u010do najv\u00e4\u010d\u0161\u00ed. T\u00e1to vlastnos\u0165 sa naz\u00fdva plnos\u0165 va\u010dky. Pod\u013ea priebehu zr\u00fdchlenia vytv\u00e1ran\u00e9ho profilom va\u010dky ich del\u00edme na spojit\u00e9 a nespojit\u00e9. Spojit\u00e9 va\u010dky z matematick\u00e9ho h\u013eadiska prezentuj\u00fa spojit\u00fa funkciu.<\/p>\n

Tvar profilu va\u010dky z\u00e1vis\u00ed od po\u017eadovan\u00fdch vlastnost\u00ed a\u00a0m\u00e1 v\u00fdrazn\u00fd vplyv na v\u00fdkon motora, obzvl\u00e1\u0161\u0165 pri vy\u0161\u0161\u00edch ot\u00e1\u010dkach. \u00dapravcovia va\u010diek z\u00e1vodn\u00fdch automobilov upravuj\u00fa, br\u00fasia, v\u00fdbe\u017eky va\u010diek tak, aby ventily zostali otvoren\u00e9 dlh\u0161ie pre udr\u017eanie prietoku vzduchu pri vy\u0161\u0161\u00edch ot\u00e1\u010dkach.<\/p>\n

Va\u010dky na hriadeli m\u00f4\u017eu by\u0165 \u0161pecificky upraven\u00e9 pre spr\u00e1vne \u010dasovanie ventilov vzh\u013eadom na pohyb piesta. \u010casovanie va\u010dkov\u00e9ho hriade\u013ea m\u00f4\u017ee by\u0165 v\u00a0predstihu, \u010d\u00edm z\u00edskame vy\u0161\u0161\u00ed to\u010div\u00fd moment pri ni\u017e\u0161\u00edch ot\u00e1\u010dkach, pr\u00edpadne oneskoren\u00e9 pre zabezpe\u010denie v\u00e4\u010d\u0161ieho v\u00fdkonu vo vy\u0161\u0161\u00edch. Mo\u017eno teda poveda\u0165, \u017ee obe mo\u017enosti menia priebeh v\u00fdkonov\u00fdch charakterist\u00edk v\u00a0celom spektre ot\u00e1\u010dok.<\/p>\n

\"IMG_6009\"<\/a><\/p>\n

Profil v\u00fdstupku va\u010diek upravuje \u010dasovanie ventilu. Vykon\u00e1vanie \u010dinnost\u00ed \u010dasovania a\u00a0ve\u013ekos\u0165 zdvihu s\u00fa d\u00f4le\u017eit\u00fdmi parametrami pri vysokov\u00fdkonn\u00fdch motoroch, ktor\u00e9 maj\u00fa men\u0161ie mo\u017enosti dodato\u010dn\u00fdch \u00faprav.<\/p>\n

Odborn\u00edk z renomovanej spolo\u010dnosti COMP Cams zaoberaj\u00facej sa \u00fapravou va\u010dkov\u00fdch hriade\u013eov, sa vyjadril, \u017ee je jednoduch\u0161ie upravova\u0165 priebeh kr\u00fatiaceho momentu pou\u017eit\u00edm upravenej va\u010dky v\u00a0pretek\u00e1rskom motore, preto\u017ee \u0161\u00edrka spektra vyu\u017e\u00edvan\u00fdch ot\u00e1\u010dok je v\u00a0t\u00fdchto motoroch omnoho men\u0161ia ako v\u00a0s\u00e9riov\u00fdch automobiloch. Ak va\u010dku upravuje na mieru pre konkr\u00e9tne \u00fazke spektrum ot\u00e1\u010dok, je v\u00fdsledok v\u00fdraznej\u0161\u00ed a\u00a0\u013eah\u0161ie pozorovate\u013en\u00fd.<\/p>\n

Nie\u010do, \u010do m\u00f4\u017ee fungova\u0165 vynikaj\u00faco v 1800kg automobile do be\u017enej prev\u00e1dzky, nemus\u00ed by\u0165 vhodn\u00e9 do 1300kg pretek\u00e1rskeho auta. Pri v\u00fdbere z\u00a0dostupn\u00fdch upraven\u00fdch va\u010diek je d\u00f4le\u017eit\u00e9 prihliada\u0165 na aplik\u00e1ciu a\u00a0nie len na kompresn\u00fd pomer a ve\u013ekos\u0165 motora. Vo\u013eba nevhodnej va\u010dky pr\u00edli\u0161 nezn\u00ed\u017ei v\u00fdkon, av\u0161ak zhor\u0161\u00ed priebeh kr\u00fatiaceho momentu. Je preto nevyhnutn\u00e9 vzia\u0165 do \u00favahy hmotnos\u0165, pou\u017eitie a\u00a0rozsah vyu\u017e\u00edvan\u00fdch ot\u00e1\u010dok vozidla.<\/p>\n

Pre n\u00e1s, Eur\u00f3panov, menej zn\u00e1my Smokey Yunick, legend\u00e1rna postava sc\u00e9ny NASCAR, tvrdil, \u017ee pretek\u00e1r si mus\u00ed vybudova\u0165 vz\u0165ah so spolo\u010dnos\u0165ou upravuj\u00facou va\u010dkov\u00e9 hriadele ak chce by\u0165 \u00faspe\u0161n\u00fdm na trati. Bolo pod\u013ea neho podstatn\u00e9, aby jazdci komunikovali s\u00a0t\u00fdmito spolo\u010dnos\u0165ami a\u00a0dr\u017eali sa ich. Firmy toti\u017e investovali mnoho prostriedkov, aby zaistili v\u00fdvoj va\u010dky k\u00a0danej aplik\u00e1cii a\u00a0v\u010faka mnohoro\u010dn\u00e9mu v\u00fdskumu a v\u00fdvoju sa stali odborn\u00edkmi vo ve\u013emi \u0161pecifickej technickej oblasti.<\/p>\n

Po\u010diatok<\/h3>\n

Trocha k hist\u00f3rii. Kon\u0161trukt\u00e9ri motorov boli informovan\u00ed o\u00a0\u010dasovan\u00ed va\u010diek a\u00a0jeho vplyve na v\u00fdkon motora u\u017e na za\u010diatku 20 storo\u010dia.<\/p>\n

Roku 1908 in\u017einieri Fordu podrobne sk\u00famali motor modelu N (predchodca sl\u00e1vneho modelu T). Spolo\u010dnos\u0165 porovn\u00e1vala va\u010dku 205\/217 (trvanie sania a\u00a0v\u00fdfuku) s\u00a0va\u010dkou 210\/224. Va\u010dka s krat\u0161\u00edm trvan\u00edm bola oneskoren\u00e1 o\u00a00,5\u00b0 a\u00a0druh\u00e1 o\u00a03,5\u00b0. Va\u010dka s\u00a0dlh\u0161\u00edm trvan\u00edm produkovala vy\u0161\u0161\u00ed v\u00fdkon, av\u0161ak krat\u0161ia poskytovala lep\u0161\u00ed priebeh momentu, v\u010faka \u010domu bola uveden\u00e1 do produkcie.<\/p>\n

Tento po\u010din m\u00f4\u017eeme pova\u017eova\u0165 za zlomov\u00fd okamih, kedy in\u017einieri pochopili v\u00fdznam a d\u00f4le\u017eitos\u0165 profilov va\u010diek a\u00a0vplyv \u010dasovania. Nasleduj\u00face desa\u0165ro\u010dia boli honom za v\u00fdkonom. Ed Winfield sa \u010dasto pova\u017euje za otca z\u00e1vodn\u00fdch va\u010diek. Pod\u013ea mnoh\u00fdch v\u00fdznamn\u00fdch osobnost\u00ed z\u00a0radov z\u00e1vodn\u00fdch in\u017einierov bol otcom pretek\u00e1rskeho automobilov\u00e9ho priemyslu.<\/p>\n

\"IMG_1357\"<\/a><\/p>\n

Ak ste v\u00a0tej dobe boli jedn\u00fdm zo \u0161\u0165astlivcov, ktor\u00ed mali Winfieldov karbur\u00e1tor, va\u010dkov\u00fd hriade\u013e alebo hlavu valcov boli ste ve\u013ek\u00fdm zviera\u0165om. Ak ste boli \u0161\u0165astlivcom nato\u013eko, \u017ee ste mali v\u0161etky uveden\u00e9 diely, pravdepodobne ste boli \u00fa\u010dastn\u00edkom najbli\u017e\u0161ej Indy 500.<\/p>\n

Za\u010diatky \u00fapravcov va\u010dkov\u00fdch hriade\u013eov<\/h3>\n

Winfieldova rodina bola finan\u010dne dobre zabezpe\u010den\u00e1 a\u00a0mlad\u00fd Ed presved\u010dil jeho matku, \u00faspe\u0161n\u00fa realitn\u00fa agentku v\u00a0LA, aby k\u00fapila pou\u017e\u00edvan\u00fa valcov\u00fa br\u00fasku. Winfield upravil zariadenie tak, aby na \u0148om mohol br\u00fasi\u0165 v\u00fdstupky va\u010diek. Prv\u00e9 br\u00fasenia prebehli na va\u010dkov\u00fdch hriade\u013eov modelov T. Upraven\u00e9 hriadele mali by\u0165 vhodn\u00e9 na okruhy, preteky mimo asfaltu a\u00a0aj pre v\u00a0tej dobe be\u017en\u00e9 klopen\u00e9 dreven\u00e9 dr\u00e1hy. Pon\u00fakal dva druhy profilov, polovi\u010dn\u00fd pretek\u00e1rsky a\u00a0pretek\u00e1rsky. Kr\u00e1tko na to sa rozhodol vytvori\u0165 profil, ktor\u00fd by zapadol medzi uveden\u00e9 typy a\u00a0nazval ho tri\u0161tvr\u0165ov\u00e1 z\u00e1vodn\u00e1 va\u010dka.<\/p>\n

Winfield bol vyu\u010den\u00fd Harrym Millerom, jedn\u00fdm z\u00a0najzn\u00e1mej\u0161\u00edch v\u00fdrobcov pretek\u00e1rskych automobilov. Harrym postaven\u00e9 automobily vyhrali Indy 500 9kr\u00e1t a\u00a0jeho motory \u010fal\u0161ie 3 razy. Ed sa u\u010dil obr\u00e1ba\u0165 diely motorov v\u00a0Millerovej dielni. V\u00a0t\u00fdchto skromn\u00fdch za\u010diatkoch sa mu podarilo vytvori\u0165 svoje vlastn\u00e9 \u0161abl\u00f3ny va\u010dkov\u00fdch hriade\u013eov a\u00a0u\u010dil ostatn\u00fdch. Povr\u00e1va sa, \u017ee Winfieldovi u\u010dni vytvorili takmer v\u0161etky spolo\u010dnosti zaoberaj\u00face sa \u00fapravami va\u010dkov\u00fdch hriade\u013eov.<\/p>\n

Jednou z\u00a0m\u00e1la v\u00fdnimiek bol Pierre Louis Betrand, priate\u013eom zn\u00e1my ako \u201ePete\u201c. Stavba pretek\u00e1rskych \u00e1ut a pretekanie sa stali jeho v\u00e1\u0161\u0148ou. V\u00a01930 odcestoval do Kalifornie so z\u00e1vo\u010f\u00e1kom na pr\u00edvese. Po nieko\u013ek\u00fdch nehod\u00e1ch zavesil helmu na klinec.<\/p>\n

Aby zostal v\u00a0bl\u00edzkosti pretekov za\u010dal upravova\u0165 va\u010dky pre miestnych. Stal sa Winfieldov\u00fdm konkurentom. Po ne\u010dakanej smrti, jeho zamestnanec Clayton \u2018Clay\u2019 Smith odk\u00fapil spolo\u010dnos\u0165 a premenoval ju na Clay Smith Cams.<\/p>\n

\"DSC_5435\"<\/a><\/p>\n

Rozmach \u00fapravcov<\/h3>\n

V\u00e4\u010d\u0161ina z\u00a0najzn\u00e1mej\u0161\u00edch v\u00fdrobcov va\u010diek spolu s\u00a0ich dod\u00e1vate\u013emi surov\u00fdch materi\u00e1lov vznikali na prelome 40 a 50 rokov a\u00a0s\u00eddlili preva\u017ene v\u00a0ju\u017enej Kalifornii. O\u00a0dek\u00e1du nesk\u00f4r za\u017eili tieto spolo\u010dnosti neuverite\u013en\u00fd rast. Niektor\u00e9 z\u00a0nich sa rozdelili, pr\u00edpadne zamestnanci vytvorili svoje vlastn\u00e9.<\/p>\n

Trh s\u00a0upraven\u00fdmi va\u010dkov\u00fdmi hriade\u013emi kop\u00edroval ve\u013ek\u00e9 zmeny. Od samotn\u00fdch za\u010diatkov, cez expl\u00f3ziu \u00e9ry musclecars a\u017e k\u00a0modern\u00fdm efekt\u00edvnym automobilom. Od bur\u00e1caj\u00facich 20. rokov sa zmenilo len m\u00e1lo. Zlep\u0161ili sa materi\u00e1ly a\u00a0zefekt\u00edvnili v\u00fdrobn\u00e9 postupy, ale va\u010dkov\u00e9 hriadele sa st\u00e1le podobaj\u00fa prvotn\u00fdm, z\u00e1vodn\u00fdm upraven\u00fdm Winfieldom. Aj ke\u010f s\u00fa na prv\u00fd poh\u013ead podobn\u00e9, v\u00a0s\u00fa\u010dasnosti je omnoho n\u00e1ro\u010dnej\u0161ie vybra\u0165 va\u010dkov\u00fd hriade\u013e pre vysokov\u00fdkonn\u00fd motor.<\/p>\n

Zamestnanec spolo\u010dnosti Crane Cams, Chase Knight vysvet\u013euje: \u201eV pretekoch je mnoho premenn\u00fdch, ako napr\u00edklad \u0161pecifick\u00e9 pravidl\u00e1 jednotliv\u00fdch skup\u00edn, tra\u0165ov\u00e9 obmedzenia, podmienky povrchu trate, rozdielne motory a\u00a0odli\u0161n\u00e9 konfigur\u00e1cie automobilu. V\u0161etky tieto parametre je potrebn\u00e9 zv\u00e1\u017ei\u0165 pri v\u00fdbere va\u010dkov\u00e9ho hriade\u013ea.\u201c<\/p>\n

Autor: Mari\u00e1n Hala\u010d; Zdroj+foto: LSXTV.com<\/p>\n

\"FullBleed\"<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Va\u010dkov\u00e9 hriadele s\u00fa s\u00fa\u010das\u0165ou stroj\u00e1rstva po st\u00e1ro\u010dia. Ich po\u010diatky siahaj\u00fa a\u017e do 3. storo\u010dia pred Kristom. V\u00a0Helenistickom obdob\u00ed boli pou\u017eit\u00e9 u vodou hnan\u00fdch automatov. Od t\u00fdchto \u010dias pre\u0161li dlh\u00fa cestu a\u00a0stali sa s\u00fa\u010das\u0165ou mnoh\u00fdch zariaden\u00ed.<\/p>\n","protected":false},"author":1,"featured_media":9802,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[4],"tags":[389,896,900,901,22,899,897,898],"class_list":["post-9800","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-dokumentarne","tag-dokument","tag-dokumentarny","tag-historia","tag-hriadel","tag-motor","tag-uprava","tag-vacka","tag-vackovy"],"translation":{"provider":"WPGlobus","version":"3.0.0","language":"de","enabled_languages":["sk","en","de"],"languages":{"sk":{"title":true,"content":true,"excerpt":false},"en":{"title":false,"content":false,"excerpt":false},"de":{"title":false,"content":false,"excerpt":false}}},"_links":{"self":[{"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/posts\/9800","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/comments?post=9800"}],"version-history":[{"count":1,"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/posts\/9800\/revisions"}],"predecessor-version":[{"id":9805,"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/posts\/9800\/revisions\/9805"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/media\/9802"}],"wp:attachment":[{"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/media?parent=9800"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/categories?post=9800"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mixmotor.eu\/de\/wp-json\/wp\/v2\/tags?post=9800"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}