@CT 1 @LM 1 @RM 65 @PL 60 @TB -----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T-----T @MT 1 @MB 1 @PO 5 @PN 1 @OP @LH 6 Teplota: 22.0o Tlak:101.0 kPa Vlhkost:60% @LH 3 @LH 6 Z.3 Stanoven statickho a dynamickho koeficientu smykovho @LH 3  ten devnch materil @LH 6  Stkaj-li se dv pevn tlesa , psob proti jejich vzjemnmu pohybu tec sla T. Vyznauje se temi zkladnmi vlastnostmi. T je pmo mrn .je koeficient smykovho ten. Nezvis na velikosti tec plochy ani na rychlosti pohybu. Vztah pro vypoet : = tg Pomcky : tribometr devn tleso zva 100g (m=99.5g) Uren statickho koeficientu smykovho ten.  Statick koeficient smykovho ten vypoteme z hodnoty meznho hlu, odetenho z hlomru na tribometru, pi kterm se tleso, voln poloen na naklomn rovin zane pohybovat. Poadavky na men: Mren provedeme s 100g pvakem a bez nj. Mezn hel mrme desetkrt. Uren dynamickho koeficientu smykovho ten  Dynamick koeficient smykovho ten urme z meznho uhlu odetenho na stupnici tribometru, pi kter se tleso pohybuje rovnomrnm pohybem po naklonn rovin. Namen hodnoty, vpoet chyb : Statick metoda  Ŀ m1  m2  Ĵ n 1  12  2  22  Ĵ 1 33.0 18.92 41.0 12.25 2 38.5 1.32 39.0 2.25 3 30.5 46.92 39.5 4.00 4 40.0 7.02 36.0 2.25 5 37.0 0.12 37.0 0.25 6 36.5 0.72 35.0 6.25 7 40.0 7.02 34.0 12.25 8 36.0 1.82 36.0 2.25 9 40.0 7.02 36.5 1.00 10 42.0 21.62 41.0 12.2 Ĵ 373.50112.53 375.00 55.00 37.35 37.5 m1= ( 62.8 + 99.5 ) g m2= 62.8 g 2 ( 1)2  = = 0.745o = 0.7o  3 n(n-1) 1 = (37.40.7)o  tg(1+ )=0.784 tg(1+ )+tg(1- ) tg(1- )=0.744 tg1 = = 0.764 2 Ŀ = tg(1+ )-tg1= 0.02 tg1= (0.76 0.02) 2 ( 2)2  = = 0.521o = 0.5o  3 n(n-1) 2 = (37,50.5)o  tg(2+ )=0.781 tg(2+ )+tg(2- ) tg(2- )=0.700 tg2 = = 0.741 2 Ŀ = tg(2+ )-tg2= 0.04 tg2= (0.74 0.04) Dynamick metoda  Ŀ m1  m2  Ĵ n 3  32  4  42  Ĵ 1 18.0 0.4356 18.0 0.2025 2 17.8 0.2116 17.9 0.1225 3 17.6 0.0676 17.8 0.0625 4 17.4 0.0036 17.7 0.0225 5 17.2 0.0196 17.6 0.0025 6 17.0 0.1156 17.5 0.0025 7 16.8 0.2916 17.4 0.0225 8 17.0 0.1156 17.3 0.0625 9 17.2 0.0196 17.2 0.1225 10 17.4 0.0036 17.1 0.2025 Ĵ 173.40 1.2840 175.50 0.8250 17.34 17.55 m1= ( 62.8 + 99.5 ) g m2= 62.8 g 2 ( 3)2  = = 0. 0796o = 0.08o  3 n(n-1) 3 = (17.340.06)o  tg(3+ )=0.3138 tg(3+ )+tg(3- ) tg(3- )=0.3107 tg3 = = 0.3123 2 Ŀ = tg(3+ )-tg3= 0.002 tg3= (0.312 0.002) 2 ( 4)2  = = 0.0638o = 0.06o  3 n(n-1) 4 = (17.550.06)o  tg(4+ )=0.3176 tg(4+ )+tg(4- ) tg(4- )=0.3149 tg4 = = 0.3163 2 Ŀ = tg(4+ )-tg4= 0.001 tg4= (0.316 0.001) Zvr: Dynamick souinitel smykovho ten je v rozmez hodnot v tabulkch. Statick souinitel smykovho ten je vt硍 ne hodnoty pro dan materily. Odchylka je zpsobena pnou na tecch plochch zkuebnho tlesa. Hodnoty souinitel se zvam a bez nj jsou tm shodn. Odchylka je piblin v toleranci. Z vpotovho vztahu a vypotench hodnot vyplv e souinitel smykovho ten nezvis na thov sle.