Name: axial load support in pivot bearings
Uploaded: 2025-05-22T09:06:04.000Z
Duration: 1 min 23 s
Channel: JoVE

Łożysko to element mechaniczny, który umożliwia względny ruch między dwiema częściami, jednocześnie zmniejszając tarcie i zużycie maszyny.
Pomaga również rozłożyć obciążenia, które mogą być promieniowe, osiowe lub stanowić kombinację obu.
Łożyska przegubowe przenoszą obciążenie osiowe na obracający się wał. Mogą mieć płaską, stożkową lub ściętą powierzchnię.
Rozważmy płaskie łożysko przegubowe poddane obciążeniu osiowemu o całkowitej powierzchni łożyska πR2.
Równomierny nacisk na łożysko jest wyrażony jako stosunek obciążenia do powierzchni łożyska.
Następnie rozważmy nieskończenie mały pierścień o promieniu r i grubości dr w obszarze łożyska; można oszacować obciążenie przenoszone na pierścień.
Teraz siła tarcia przeciwstawiająca się przesuwaniu się pierścienia działa stycznie w promieniu r.
Tak więc, obliczając moment pierścienia i integrując go w granicach promieniowych, można oszacować moment wału, który jest wymagany do pokonania sił tarcia.

<ol>
	<li>Hibbeler, R.C. (2016). Mechanika inżynierska \u2012 Statyka i dynamika. Hoboken, New Jersey: Pearson Prentice Hall. Strona 447.</li>
</ol>

Łożyska obrotowe

Pivot Bearings

W systemach mechanicznych łożyska mają kluczowe znaczenie w ułatwianiu ruchu względnego pomiędzy dwoma komponentami, jednocześnie minimalizując tarcie i zużycie elementów. Pomagają rozprowadzać różne obciążenia (promieniowe, osiowe lub ich kombinację) na części maszyn, zapewniając płynne i wydajne działanie.

Łożysko obrotowe to specjalny rodzaj łożyska zaprojektowany do przeciwdziałania obciążeniom osiowych na obrotowym wałku. Powierzchnia łożyska, czyli oś obrotu, jest umieszczona na końcu wałka w celu podtrzymywania siły osiowej. Oś obrotu może mieć płaską, stożkową lub przyciętą powierzchnię w zależności od zastosowania.

W płaskim łożysku obrotowym, gdy jest poddane obciążeniu osiowemu, jednolite ciśnienie wywierane na łożysko można obliczyć jako stosunek obciążenia do powierzchni łożyska. Rozkład tego ciśnienia pomaga zminimalizować tarcie i zużycie na powierzchni łożyska, przyczyniając się do bardziej wydajnego działania i dłuższego czasu użytkowania.

Aby dokładniej zbadać siły działające na płaskie łożysko obrotowe, możemy przeanalizować nieskończoną pierścieniową powierzchnię w obrębie obszaru łożyska o promieniu r i grubości dr. Obciążenie przekazywane temu pierścieniowi można oszacować na podstawie rozkładu ciśnienia na powierzchni łożyska.

Kiedy wałek obraca się, siły tarcia przeciwdziałają ślizganiu pierścienia i działają stycznie na promieniu r, obliczając moment pierścienia i całkując go w granicach promienia, można określić moment wałka, jak pokazano poniżej:

<img alt="Equation 1" src="/files/ftp_upload/14324/14324_Equation_1v2.svg" style="text-align: center; height: 28px;" />

To obliczenie dostarcza cennych informacji na temat wydajności i efektywności łożyska w zmiennych warunkach obciążenia.

Łożyska obrotowe są wykorzystywane w różnorodnych branżach i systemach mechanicznych ze względu na ich unikalną zdolność do podtrzymywania obciążeń osiowych na obrotowych wałkach. Te wszechstronne komponenty można znaleźć w maszynach obrotowych takich jak turbiny, generatory, pompy oraz w komponentach samochodowych takich jak układy kierownicze i zespoły przekładni. Ponadto, łożyska obrotowe, w tym podwozia samolotów oraz powierzchnie kontrolne lotu, są niezbędne w aplikacjach lotniczych. Urządzenia przemysłowe, takie jak żurawie, wciągniki i przenośniki, również polegają na łożyskach obrotowych dla efektywnego działania i niezawodnej wydajności. W rezultacie szerokie zastosowanie łożysk obrotowych w różnych branżach podkreśla ich znaczenie w utrzymaniu płynnych i efektywnych systemów mechanicznych.

W układach mechanicznych łożyska odgrywają kluczową rolę w ułatwianiu względnego ruchu między dwoma komponentami przy jednoczesnej minimalizacji tarcia i zużycia. Pomagają ...

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axial load support in pivot bearings

Pivot bearings support axial loads on a rotating shaft. A bearing helps two parts move relative to each other while reducing friction and wear. In this design, the pivot is placed at the end of the shaft to carry the axial thrust.

The pivot surface can be flat, conical, or truncated, depending on the application. In a flat pivot bearing, the axial load is spread over the bearing area. The pressure is uniform and can be found by dividing the load by the area.

To study the forces more closely, engineers can look at a tiny ring inside the bearing surface. This ring has a radius r and a small thickness dr. The load on the ring depends on the pressure across the bearing area.

As the shaft turns, friction acts on the ring and resists sliding. This force acts tangentially at radius r. By finding the moment of the ring and integrating across the radial limits, the moment of the shaft can be determined. This helps explain how the bearing performs under different load conditions.

Pivot bearings are used in many machines and industries. They appear in turbines, generators, pumps, steering systems, and transmission assemblies. They are also important in aerospace parts such as landing gear and flight control surfaces, as well as in cranes, winches, and conveyors.

Axial Load Support in Pivot Bearings

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pivot bearings

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collar bearings

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key terms and concepts

Learn how pivot bearings support axial loads on rotating shafts, reduce friction, and appear in turbines, generators, pumps, cars, aircraft, and industrial equipment.

Axial Load Support in Pivot Bearings | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

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Axial Load Support in Pivot Bearings

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