W pracy przedstawiona została nowa konstrukcja amortyzowanego uchwytu sprężyny śrubowej. Konstrukcja ta ma wiele zalet w stosunku do istniejących rozwiązań. Przeprowadzone w pracy symulacje MES wykazały, że w porównaniu z konwencjonalnym uchwytem mocującym, konstrukcja ta zapewnia niski poziom naprężeń maksymalnych zarówno w sprężynie, jak i w samym uchwycie. Wykazano również, że amortyzująca część uchwytu może być wykonana z materiału elstomerowego o właściwościach wytrzymałościowych zbliżonych do typowych gum stosowanych w przemyśle. Przedstawiono możliwości aplikacyjne omawianego rozwiązania konstrukcyjnego.
EN
New design of amortized grip of the helical spring was presented. Presented design as many advantages over existing solutions. FEM simulations showed that, compared with a conventional clamping device, this design provides a Iow level of maximum stress, in both the spring and in the grip. It was also demonstrated that the amortized part of the grip could be made of elastomer material with strength properties similar to those observed for rubbers commonly used in the industry. There were presented possibilities of application of this design solution.
Coil springs do not always has regular geometry with constant pitch and constant mean diameter. Geometry of spring is more complex. Furthermore, spring stiffness could change with deflection. That makes calculation of spring stiffness more complicated than just putting four values into mathematical formula. In article has been presented two investigation methods of spring characteristic. Investigated object is a passenger vehicle suspension coil spring. Recognition spring characteristic is primary stage of vehicle dynamic suspension simulation. It has a very big impact on the vehicle height, comfort, handling and safety of vehicle. It is often assumed that vehicle spring has constant stiffness coefficient, which is sometimes a reason of incorrect suspension model. Vehicle springs rather has a progressive characteristic than linear. One of presented method is traditional, experimental compression test. Second, one is a measurement and modelling of spring geometry. Than analysing it in finite element method (FEM) simulation. Comparison has been done to check property of FEM process. Computed compression has been done in ABAQUS CAE 6.13-1 software. Analysis has shown that process of analysing is useful. There were obtained a good agreement between experimental research and computed model. In spite of irregular spring geometry, final characteristic is close to linear. Progressiveness is visible but not high.
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This paper deals with a theoretical description of coil helical springs rigidity and with experimental spring determination on model. This experiment is instrumental in theoretical expectation verification. Experimental measurement of spring rigidity has been performed.
PL
Artykuł zawiera metodykę i opis stanowiska do badań własności sprężystych sprężyn śrubowych. Dla przykładu załączono wyniki badań sztywności wybranych wielkości sprężyn.
It is shown in this paper that the proposed concept by Krużelecki and Życzkowski (1990) of the equivalent rod can be applied in calculations of natural lateral vibrations of springs and that the obtained results will be nearer FEM results than the standard model based on the Timoshenko equivalent beam. The model, created on this base, allows one to calculate natural frequencies of the clamped-clamped spring. It is also shown that models based on the equivalent beam concept, which are easier to apply than the models treating the spring as the spatially curved rod, have only a slightly smaller accuracy. It is also indicated that in the most common practice making of manufacturing end coils of springs, the natural frequencies differ significantly from the frequencies calculated by means of all tested methods. The performed simulations show that differences between the first and the second as well as the third and the fourth natural frequency of the spring are small and, therefore, the axially symmetrical equivalent beam model can be used without a large error. The diagram allowing one to determine whether the desired frequencies are lower or higher than the cut-off frequency is developed for the presented model.
The analysis of elastomeric coating influence on dynamic resonant stresses values in spring is presented in this paper. The appropriate equations determining the effectiveness of dynamic stress reduction in resonant conditions as a function of coating parameters were derived. It was proved that rubber coating will not perform in satisfactory manner due to its low modulus of elasticity in shear. It was also demonstrated that about-resonance areas of increased stresses are wider and wider along with the successive resonances and achieve significant values even at large distances from the resonance frequencies.
W artykule przedstawiono zagadnienia zwiększenia wytrzymałości zmęczeniowej sprężyn śrubowych usprężynowania pierwszego stopnia wózków wagonów towarowych Y25L. Zwiększenie wytrzymałości zmęczeniowej można osiągnąć dobierając odpowiednio materiał pręta oraz stosując zabiegi technologiczne. Omówiono czynniki, które przyczyniają się do zwiększenia żywotności sprężyn, jak np. prawidłowe użycie tłumika ciernego czy też zabezpieczenie antykorozyjne.
EN
The article presents the issues of increasing the fatigue strength of the screw springs of the primary suspension of the freight wagon bogies Y25L. The increasing of fatigue strength can be achieved by the proper selection of material of the rod and applying the technological treatments. The factors that cause the increase of spring life, for example correct use of the friction damper or corrosion protection, are discussed.
W artykule przedstawiono dalszą problematykę sprężyn śrubowych zawieszenia pierwszego stopnia wózków wagonów towarowych typu Y25 w świetle obliczeń wytrzymałościowych, technologii wykonania, właściwego doboru materiału na wykonanie sprężyn zawieszenia pierwszego stopnia oraz niektórych doświadczeń eksploatacyjnych. Obliczenia wytrzymałościowe przeprowadzono dla obciążeń pionowych i poprzecznych działających na sprężynę zewnętrzną i wewnętrzną.
EN
The article presents the further problems of coil springs of the first suspension of the freight wagons bogies type Y25 in the light of strength calculations, the technology of carrying out, the proper selection of material for the execution of the first suspension of springs and some operational experiences. Strength calculations were performed for vertical and lateral loads acting on the outer and inner spring.
The paper presents an experimental device that was created in order to obtain the real values of the forces acting in the vertical direction on the lock‑off element, the so‑called brake body, the 2nd design option. The lock of this design is used in the automated parking garage, designed by KOMA – Industry, s.r.o, to lock the parked vehicles on pallets in the units of the rack parking system. The forces acting in the vertical direction on the body of the fixation lock when pushing the brake pulley into the circular recess in the brake ramp are theoretically calculated for two design variants of the brake ramp used in practice, i.e. “without” and “with” a rounded (filleted) circular recess segment in the brake ramp. The experimentally determined forces acting in the vertical direction on the brake body were determined for two types of compression coil springs with a rectangular cross section of the spring wire.
Przedstawiono ogólną budowę ustrojów nośnych i zawieszeń samochodów ciężarowo-osobowych wysokiej mobilności eksploatowanych w pododdziałach Sił Zbrojnych RP. Zamieszczono również aktualny podział pojazdów. Opis wzbogacono rysunkami i danymi tabelarycznymi. W treści scharakteryzowano wady i zalety przyjętych rozwiązań konstrukcyjnych omawianych pojazdów.
EN
The article discusses the general construction of load-carrying structures and suspensions in high mobility cargo and passenger carrying vehicles operated by the Polish Armed Forces. As well as this, a current classification of vehicles is presented. The description is expanded with figures and tables. The pros and cons of the adopted technical solutions are discussed.
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