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

Düz bir kayış, yarıçapları sırasıyla 30 cm ve 10 cm olan A ve B olmak üzere iki kasnağın etrafına sarılır.
Kasnaklarda kayış ile yatay arasındaki açı 20 derecedir.
Kasnak B saat yönünde döner ve Kasnak A'yı hareket ettirerek kayışın bir ucunda T2 gerilimine ve diğer ucunda T1 gerilimine neden olur.
İzin verilen maksimum gerilim T2'nin 1000 N ve kayış ile kasnaklar arasındaki statik sürtünme katsayısının 0.4 olduğu göz önüne alındığında, kasnak A'daki maksimum moment nedir?
Sistemin geometrisinden hesaplanan kayış-yüzey temas açısı 140 derecedir.
Radyan cinsinden kayış-yüzey temas açısı ve statik sürtünme katsayısı değerleri, T1 elde etmek için kayış gerilimleri ifadesine ikame edilir.
Kasnak B saat yönünde dönerken, kasnak B'de oluşan bir gerilim farkı, kasnak A'da bir moment oluşturur.
Kasnak A için bir serbest cisim diyagramı çizilir ve moment denge koşulu uygulanır.
Maksimum momenti elde etmek için yarıçap ve gerilim değerleri ikame edilir.

<ol>
	<li>Hibbeler, R.C. (2016). Mühendislik Mekaniği \u2012 Statik ve Dinamik. Hoboken, New Jersey: Pearson Prentice Salonu. Sayfa 439 \u2012 441.</li>
	<li>Meriam, J.L.; Kraige, L.G. ve Bolton, J.N. (2020). Mühendislik Mekaniği \u2012 Statik. Hoboken, New Jersey: John Wiley. Sayfa 372.</li>
	<li>Bira, F.P.; Johnston, E.R.; Mazurek, D.F; Cromwell, P.J. ve Öz, B.P. (2019). Mühendisler için Vektör Mekaniği \u2012 Statik ve Dinamik. New York: McGraw-Tepesi. Sayfa 469-470.</li>
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düz kayışlar: sorun Çözme

Flat Belts: Problem Solving

Düz kayışlar endüstriyel birçok uygulamada önemli bir role sahiptir çünkü gücü bir kasnakten diğerine iletmeye yardımcı olurlar. Momentlerin ve kuvvetlerin kavramı, bir kasnak üzerindeki maksimum momenti belirlemek için kullanılır. Örneğin, 30 cm ve 10 cm yarıçaplı A ve B kasnaklarına sarılan bir düz kayışı düşünelim. Kayışın yatayla yaptığı açı, kasnaklarda 20 derecedir. Kasnak B saat yönünde dönerken kasnağı A sürerken, bir uçta T2 gerilimi, diğer uçta ise T1 gerilimi oluşur.

<img alt="Figure 1" src="/files/ftp_upload/14323/14323_PT_Fig_1v2.svg" style="text-align: center; height: 250px;" />

Kayış-yüzey temas açısı, β, maksimum momenti belirlemek için hesaplanmalıdır. Bu açı, sistemin geometrisinden elde edilir ve 140 derece bulunur. Sonuç olarak, kayış-yüzey temas açısı radyan cinsinden ifade edilir ve statik sürtünme katsayısı olan 0.4 ile birlikte kayış gerilimleri için ifadeye yerleştirilir.

<img alt="Equation 1" src="/files/ftp_upload/14323/14323_PT_Equation_1v2.svg" style="text-align: center; height: 35px;" />

Maksimum izin verilen T2 gerilimi 1000 N olduğu düşünüldüğünde, hesaplanan T1 değeri 376.93 N'dir. Kasnak B saat yönünde dönerken kasnak B'de bir gerilim farkı oluşur ve bu da kasnak A'da bir moment oluşturur. Kasnak A'ya yönelik bir serbest cisim diyagramı göz önüne alındığında, moment dengesi koşulu uygulanabilir.

<img alt="Equation 2" src="/files/ftp_upload/14323/14323_PT_Equation_2v2.svg" style="text-align: center; height: 13px;" />

Yarıçap ve gerilim değerleri ardışık olarak yerleştirilerek maksimum moment 186.921 N.m olarak elde edilir.

Düz Kayışlar: Sorun Çözme

Düz kayışlar, gücün bir kasnaktan diğerine iletilmesine yardımcı oldukları için birçok endüstriyel uygulamada çok önemlidir. Kuvvetler ve momentler kavramı kullanılır ...

Education

JoVE Core

Mechanical Engineering

Makine Mühendisliği

Unit 1

Ünite 1

Friction

Sürtünme

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

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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flat belts: problem solving

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,...

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key terms and concepts

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

JoVE Core Makine Mühendisliği, denge, kuvvetler, kafes kiriş analizi ve yapısal mekanik gibi temel konuları kapsayan kısa, anlaşılması kolay animasyonlu videolar sunar. Gerçek dünyadaki uygulamalarını keşfedin ve bilim insanlarının önderlik ettiği deneylerle bu kavramların uygulanmasına tanık olun.

mechanical engineering

Flat Belt Forces and Pulley Moment

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