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

평평한 벨트는 각각 30cm와 10cm의 반경을 가진 두 개의 도르래 A와 B를 감쌉니다.
벨트와 수평 사이의 각도는 풀리에서 20도입니다.
풀리 B는 시계 방향으로 회전하여 풀리 A를 구동하여 벨트의 한쪽 끝에서 장력 T2 를 유발하고 다른 쪽 끝에서 장력 T1 을 유발합니다.
최대 허용 장력 T2 가 1000 N이고 벨트와 풀리 사이의 정적 마찰 계수가 0.4 인 경우 풀리 A의 최대 모멘트는 얼마입니까?
시스템의 형상에서 계산된 벨트와 곡면 접촉각은 140도입니다.
벨트와 곡면 접촉각(라디안)과 정적 마찰 계수 값은 벨트 장력에 대한 표현식으로 대체되어 T1을 얻습니다.
풀리 B가 시계 방향으로 회전하면 풀리 B에서 생성된 장력 차이가 풀리 A에서 모멘트를 생성합니다.
풀리 A에 대한 자유물체 다이어그램이 그려지고 모멘트 평형 조건이 적용됩니다.
반경 및 장력 값은 최대 모멘트를 얻기 위해 대체됩니다.

<ol>
	<li>히벨러, R.C. (2016). Engineering Mechanics \u2012 정역학 및 동역학. 뉴저지 호보켄: 피어슨 프렌티스 홀. 439쪽 - 441쪽.</li>
	<li>메리암, J.L.; Kraige, L.G. 및 Bolton, J.N. (2020). 엔지니어링 역학 \u2012 정역학. 뉴저지 호보켄: 존 와일리. 372쪽.</li>
	<li>맥주, F.P.; 존스턴, ER; 마주렉, D.F; 크롬웰, PJ 및 셀프, BP (2019). 엔지니어를 위한 벡터 역학 \u2012 Statics and Dynamics. 뉴욕 : McGraw-Hill. 469-470쪽.</li>
</ol>

플랫 벨트: 문제 해결

Flat Belts: Problem Solving

평평한 벨트는 한 도르래에서 다른 도르래로 동력을 전달하는 데 도움을 주기 때문에 많은 산업 응용 분야에서 중요합니다. 힘과 모멘트의 개념은 도르래의 최대 모멘트를 결정하는 데 사용됩니다. 예를 들어, 반경이 각각 30cm와 10cm인 두 도르래 A과 B을 감싸는 평평한 벨트를 생각해 보세요. 벨트와 수평 사이의 각도는 도르래에서 20도입니다. 도르래 B가 시계 방향으로 회전하여 도르래 A을 구동하면 벨트의 한쪽 끝에 장력 T2이 발생하고 다른 쪽 끝에 장력 T이 발생합니다.

<img alt="Figure 1" src="/files/ftp_upload/14323/14323_PT_Fig_1v2.svg" style="text-align: center; height: 250px;">

최대 모멘트를 결정하기 위해서는 벨트-표면 접촉각, β을 계산해야 합니다. 이 각도는 시스템의 기하학적 구조로부터 얻어지며, 140도임을 알 수 있습니다. 따라서, 라디안 단위의 벨트-표면 접촉각은 정지마찰값의 계수인 0.4와 함께 벨트 장력에 대한 식으로 대체됩니다.

<img alt="Equation 1" src="/files/ftp_upload/14323/14323_PT_Equation_1v2.svg" style="text-align: center; height: 35px;" />

최대 허용 장력 T2이 1000N임을 고려하면, 계산된 T1의 값은 376.93N입니다. 도르래B가 시계 방향으로 회전함에 따라 도르래 B에 장력 차이가 발생하여 도르래 A에 모멘트가 발생합니다. 도르래 A에 대한 자유 물체 다이어그램을 고려하면, 모멘트 평형 조건이 적용될 수 있습니다. 

<img alt="Equation 2" src="/files/ftp_upload/14323/14323_PT_Equation_2v2.svg" style="text-align: center; height: 13px;" />

그런 다음 반지름과 장력 값을 대입하여 최대 모멘트를 186.921 N.m 로 얻습니다.

플랫 벨트는 한 풀리에서 다른 풀리로 동력을 전달하는 데 도움이 되기 때문에 많은 산업 응용 분야에서 매우 중요합니다. 힘과 모멘트의 개념이 사용됩니다 ...

Education

교육

JoVE Core

Mechanical Engineering

기계공학

Unit 1

제1단원

Friction

마찰

KEY TERMS AND CONCEPTS

주요 용어 및 개념

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

dry friction

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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,...

pivot bearings

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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 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

Flat Belt Forces and Pulley Moment

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