20.500.12556/RUL-95504 Razvoj in umerjanje preizkuševališča za določanje vzmetne konstante tlačnih vijačnih vzmeti Development and calibration of a test bench for determination of spring constant of compression helical springs V nalogi obravnavamo zasnovo, izdelavo, umerjanje in test preizkuševališča za določanje vzmetne konstante tlačnih vijačnih vzmeti specifične geometrije. Na podlagi pregleda literature smo skonstruirali horizontalno preizkuševališče s pnevmatskim valjem kot aktuatorjem za obremenjevanje vzmeti. V preizkuševališče smo vgradili merilno celico z uporovnimi lističi za merjenje sile in potenciometrično zaznavalo pomika za merjenje skrčka vzmeti. Merilna zaznavala smo pred vgradnjo umerili in določili merilno negotovost merjenja pomika ter sile; preko slednjih parametrov smo na podlagi izmerkov računali vzmetno konstanto različnih (ne)linearnih tlačnih vijačnih vzmeti. Ugotovili smo, da preizkuševališče omogoča dobro ponovljivost meritev, katerih merilna negotovost je primerljiva z meritvami na industrijskih preizkuševališčih. Preko meritev na šesti vzmeteh smo potrdili obstoj histereze pri obremenjevanju oz. razbremenjevanju in ugotovili, da za popis karakteristike vzmeti zadostuje polinom tretje stopnje, katerega prvi odvod predstavlja koeficient vzmeti kot funkcijo. In this work, we deal with the design, manufacture, calibration and testing of a test bench, design for determination of spring constant of helical compression springs with a specific geometry. Based on literature review, we designed a horizontal test bench, which utilizes a pneumatic cylinder as the actuator for spring compression. On the test bench, we installed a load cell for force measurement and a potentiometric linear displacement sensor for distance measurement. Sensors were calibrated prior to the installation and the measurement uncertainty of force and displacement measurements was calculated based on calibration results. Both of these parameters were used to calculate the spring constant of (non-)linear helical compression springs. We determined that our test bench provides good repeatability of measurements with the measurement uncertainty comparable to that of industrial test benches. Based on the measurements performed on six springs we confirmed the existence of a loading and unloading hysteresis and found that the characteristic curve of a spring can be approximated using a third-degree polynomial with the first derivative of the latter representing the spring coefficient as a function. koeficient vzmeti vijačna vzmet umerjanje merjenje sile merjenje pomika Hookov zakon spring constant helical spring calibration force measurement linear displacement measurement Hooke's law true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2017-09-20 14:54:21 2017-09-20 14:54:22 2023-11-29 13:02:46 0000-00-00 00:00:00 2017 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 1970-01-01 201320 1170.pdf 1170.pdf 1 E933737019BC6DDD92B672A8EC1BCEF0 0233448aa6f37d091283b347b2f9648fb76893073ca1f14ecbdc521f7fecce50 c5ab22e8-a1b3-11eb-a523-00155dcfd717 20.500.12556/rul/eafb9648-69f1-4f73-b0df-2ca6bd4fb33e https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=104109 Fakulteta za strojništvo 0 0 0