Name: flat belt forces and pulley moment
Uploaded: 2023-09-22T11:49:30.000Z
Duration: 1 min 28 s
Channel: JoVE

Una correa plana se envuelve alrededor de dos poleas, A y B, con radios de 30 cm y 10 cm, respectivamente.
El ángulo entre la correa y la horizontal es de 20 grados en las poleas.
La polea B gira en el sentido de las agujas del reloj e impulsa la polea A, lo que provoca una tensión T2 en un extremo de la correa y una tensión T1 en el otro.
Dado que la tensión máxima permitida T2 es de 1000 N y el coeficiente de fricción estática entre la correa y las poleas es de 0,4, ¿cuál es el momento máximo en la polea A?
El ángulo de contacto de la correa con la superficie, calculado a partir de la geometría del sistema, es de 140 grados.
El ángulo de contacto de la correa a la superficie en radianes y el coeficiente de los valores de fricción estática se sustituyen en la expresión de las tensiones de la correa para obtener T1.
A medida que la polea B gira en el sentido de las agujas del reloj, una diferencia de tensión creada en la polea B genera un momento en la polea A.
Se dibuja un diagrama de cuerpo libre para la polea A y se aplica la condición de equilibrio de momento.
Los valores de radio y tensión se sustituyen para obtener el momento máximo.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. Págs. 439 \u2012 441.</li>
	<li>Meriam, J.L.; Kraige, L.G. y Bolton, J.N. (2020). Ingeniería Mecánica \u2012 Estática. Hoboken, Nueva Jersey: John Wiley. Págs. 372.</li>
	<li>Cerveza, F.P.; Johnston, E.R.; Mazurek, D.F.; Cromwell, P.J. y Self, B.P. (2019). Mecánica vectorial para ingenieros: estática y dinámica. Nueva York: McGraw-Hill. Págs. 469-470.</li>
</ol>

correas planas: solución de problemas

Flat Belts: Problem Solving

Las correas planas son fundamentales en muchas aplicaciones industriales ya que ayudan a transmitir la potencia de una polea a otra. El concepto de fuerzas y momentos se utiliza para determinar el momento máximo en una polea. Por ejemplo, consideremos una correa plana que se enrolla alrededor de dos poleas, A y B, con radios de 30 cm y 10 cm respectivamente. El ángulo entre la correa y la horizontal es de 20 grados en las poleas. A medida que la polea B gira en sentido horario y mueve la polea A, se crea una tensión T2 en un extremo de la correa, mientras que se crea una tensión T1 en el otro. <img alt="Figure 1" src="/files/ftp_upload/14323/14323_PT_Fig_1v2.svg" style="text-align: center; height: 250px;"> El ángulo de contacto correa-superficie, β, debe calcularse para determinar el momento máximo. Este ángulo se obtiene a partir de la geometría del sistema y se encuentra que es de 140 grados. Como resultado, el ángulo de contacto correa-superficie en radianes, junto con el valor del coeficiente de fricción estática, 0.4, se sustituyen en la expresión de las tensiones de la correa. <img alt="Equation 1" src="/files/ftp_upload/14323/14323_PT_Equation_1v2.svg" style="text-align: center; height: 35px;"> Considerando que la tensión máxima permitida T2 es de 1000 N, el valor calculado de T1 es de 376.93 N. A medida que la polea B gira en sentido horario, se crea una diferencia de tensión en la polea B, generando un momento en la polea A. Considerando un diagrama de cuerpo libre para la polea A, se puede aplicar la condición de equilibrio de momentos. <img alt="Equation 2" src="/files/ftp_upload/14323/14323_PT_Equation_2v2.svg" style="text-align: center; height: 13px;"> Los valores de radio y tensión se sustituyen posteriormente para obtener el momento máximo como 186.921 N.m.

Correas planas: Solución de problemas

Las correas planas son cruciales en muchas aplicaciones industriales, ya que ayudan a transmitir la potencia de una polea a otra. Se utiliza el concepto de fuerzas y momentos ...

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flat belt forces and pulley moment

Flat belts transmit power from one pulley to another, and the forces on the belt help determine the moment on a pulley. In this example, a belt wraps around pulleys A and B, with radii of 30 cm and 10 cm. The belt meets the pulleys at a 20 degree angle from the horizontal, which sets up the force balance in the system.

As pulley B rotates clockwise, it drives pulley A. That motion creates tension T2 on one side of the belt and tension T1 on the other side. The belt-to-surface contact angle, β, is needed to find the maximum moment, so it is first found from the geometry of the setup. The angle is 140 degrees.

Next, the contact angle in radians and the coefficient of static friction, 0.4, are used in the belt tension equation. With the maximum allowable tension T2 set to 1000 N, the value of T1 is calculated as 376.93 N. A free-body diagram for pulley A then helps apply moment equilibrium. Using the pulley radius and the belt tensions, the maximum moment is found to be 186.921 N.m.

Flat Belt Forces and Pulley Moment

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Learn how belt tension, friction, and pulley radius are used to calculate the maximum moment in a flat belt drive system with two pulleys.

Flat Belt Forces and Pulley Moment | JoVE K12

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Flat Belt Forces and Pulley Moment

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