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

Un rodamiento es un elemento mecánico que permite el movimiento relativo entre dos partes al tiempo que reduce la fricción y el desgaste de la maquinaria.
También ayuda a distribuir cargas, que pueden ser radiales, axiales o una combinación de ambas.
Los cojinetes de pivote soportan una carga axial en un eje giratorio. Pueden tener una superficie plana, cónica o truncada.
Considere un rodamiento de pivote plano sometido a una carga axial con un área total de apoyo de πR2.
La presión uniforme sobre el rodamiento se expresa como la relación de la carga sobre el área del rodamiento.
A continuación, considere un anillo infinitesimal de radio r y espesor dr dentro del área del rodamiento; se puede estimar la carga transmitida al anillo.
Ahora, la fuerza de fricción que resiste el deslizamiento del anillo actúa tangencialmente en el radio r.
Entonces, al calcular el momento del anillo e integrarlo dentro de los límites radiales, se puede estimar el momento del eje, que se requiere para superar las fuerzas de fricción.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. Págs. 447.</li>
</ol>

cojinetes de pivote

Pivot Bearings

En los sistemas mecánicos, los cojinetes son cruciales para facilitar el movimiento relativo entre dos componentes mientras se minimiza la fricción y el desgaste. Ayudan a distribuir varias cargas (radiales, axiales o una combinación de ambas cargas) en piezas de maquinaria, asegurando un funcionamiento suave y eficiente. Un cojinete de pivote es un tipo especializado de cojinete diseñado para soportar cargas axiales en un eje giratorio. La superficie del cojinete, o el pivote, está posicionado en el extremo de un eje para soportar la carga axial. El pivote puede tener una superficie plana, cónica o truncada dependiendo de la aplicación. En un cojinete de pivote plano, cuando se somete a una carga axial, la presión uniforme ejercida sobre el cojinete se puede calcular como la relación entre la carga y el área del cojinete. Esta distribución de presión ayuda a minimizar la fricción y el desgaste en la superficie del cojinete, contribuyendo a un funcionamiento más eficiente y una vida útil más larga. Para analizar aún más las fuerzas que actúan sobre un cojinete de pivote plano, podemos examinar un anillo infinitesimal dentro del área del cojinete, con un radio r y un grosor dr. La carga transmitida a este anillo se puede estimar en función de la distribución de presión en la superficie del cojinete. A medida que el eje gira, las fuerzas de fricción resisten el deslizamiento del anillo y actúan tangencialmente en el radio r. Al calcular el momento del anillo e integrarlo dentro de los límites radiales, se puede determinar el momento del eje de la siguiente manera: <img alt="Equation 1" src="/files/ftp_upload/14324/14324_Equation_1v2.svg" style="text-align: center; height: 28px;"> Este cálculo proporciona información valiosa sobre el rendimiento y la eficiencia del cojinete bajo diferentes condiciones de carga. Los cojinetes de pivote se utilizan en una amplia variedad de industrias y sistemas mecánicos debido a su capacidad única de soportar cargas axiales en ejes giratorios. Estos componentes versátiles se pueden encontrar en maquinaria giratoria como turbinas, generadores, bombas y componentes automotrices como sistemas de dirección y ensambles de transmisión. Además, los cojinetes de pivote, incluyendo el tren de aterrizaje y las superficies de control de vuelo, son cruciales en aplicaciones aeroespaciales. El equipo industrial, como grúas, cabrestantes y transportadores, también depende de los cojinetes de pivote para un funcionamiento eficiente y un rendimiento confiable. Como resultado, el uso generalizado de los cojinetes de pivote en diversos sectores destaca su importancia en mantener sistemas mecánicos suaves y efectivos.

Cojinetes de pivote

En los sistemas mecánicos, los rodamientos son cruciales para facilitar el movimiento relativo entre dos componentes y, al mismo tiempo, minimizar la fricción y el desgaste. Ayudan ...

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Friction

Fricción

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

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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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.

mechanical engineering

Axial Load Support in Pivot Bearings

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