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

Подшипник — это механический элемент, который обеспечивает относительное движение между двумя частями при одновременном снижении трения и износа оборудования.
Он также помогает распределять нагрузки, которые могут быть радиальными, осевыми или их комбинацией.
Шарнирные подшипники выдерживают осевую нагрузку на вращающийся вал. Они могут иметь плоскую, коническую или усеченную поверхность.
Рассмотрим подшипник плоского шарнира, на который действует осевая нагрузка, общая площадь подшипника πR2.
Равномерное давление на подшипник выражается как отношение нагрузки к площади подшипника.
Затем рассмотрим бесконечно малое кольцо радиуса r и толщины dr в пределах области подшипника; можно оценить нагрузку, передаваемую на кольцо.
Теперь сила трения, препятствующая скольжению кольца, действует по касательной в радиусе r.
Так, рассчитав момент кольца и интегрируя его в радиальные пределы, можно оценить момент вала, который требуется для преодоления сил трения.

<ol>
	<li>Хиббелер, Р.К. (2016). Инженерная механика \u2012 Статика и динамика. Хобокен, Нью-Джерси: Пирсон Прентис Холл. С. 447.</li>
</ol>

Поворотные подшипники

Pivot Bearings

В механических системах подшипники являются важными элементами, обеспечивающими относительное движение между двумя компонентами при минимизации трения и износа. Они помогают распределять различные нагрузки (радиальные, осевые или комбинированные) по частям механизмов, обеспечивая плавную и эффективную работу.

Поворотный подшипник является специализированным типом подшипника, разработанным для поддержки осевых нагрузок на вращающемся валу. Подшипниковая поверхность, или опора, располагается на конце вала для поддержки осевого усилия. Форма опоры может быть плоской, конической или усеченной, в зависимости от применения.

В плоском поворотном подшипнике при действии осевой нагрузки равномерное давление, оказываемое на подшипник, может быть рассчитано как отношение нагрузки к площади подшипника. Распределение этого давления помогает минимизировать трение и износ подшипниковой поверхности, способствуя более эффективной работе и длительному сроку службы.

Для дальнейшего анализа действующих сил на плоский поворотный подшипник можно рассмотреть бесконечное кольцо в пределах подшипниковой площади с радиусом r и толщиной dr. Нагрузка, передаваемая этому кольцу, может быть оценена на основе распределения давления по поверхности подшипника.

При вращении вала силы трения сопротивляются скольжению кольца и действуют касательно на радиус r. Путем расчета момента кольца и интегрирования его в пределах радиальных границ можно определить момент вала следующим образом:

<img alt="Equation 1" src="/files/ftp_upload/14324/14324_Equation_1v2.svg" style="text-align: center; height: 28px;" />

Этот расчет дает ценную информацию о работе и эффективности подшипника при различных условиях нагрузки.

Поворотные подшипники применяются в различных отраслях промышленности и механических системах благодаря своей уникальной способности поддерживать осевые нагрузки на вращающихся валах. Эти универсальные компоненты могут быть найдены во вращающихся механизмах, таких как турбины, генераторы, насосы и автомобильные компоненты, такие как системы управления рулевым управлением и трансмиссии. Кроме того, поворотные подшипники, включая шасси и управляющие поверхности полета, играют важную роль в авиационной промышленности. Промышленное оборудование, такое как краны, лебедки и конвейеры, также полагается на поворотные подшипники для эффективной работы и надежной производительности. Таким образом, широкое применение поворотных подшипников в различных секторах подчеркивает их важность для поддержания плавной и эффективной работы механических систем.

В механических системах подшипники играют решающую роль в обеспечении относительного движения между двумя компонентами при минимизации трения и износа. Они помогают...

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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

dry friction

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kinetic friction

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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,...

collar bearings

Friction Torque in 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

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Axial Load Support in Pivot Bearings

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