Name: toggle clamp force analysis
Uploaded: 2023-09-22T11:49:25.000Z
Duration: 1 min 22 s
Channel: JoVE

Considere um grampo de alternância submetido a uma força de 200 Newton na alça.
Qual é a força de aperto vertical, desde que as dimensões do grampo de alternância sejam conhecidas?
Este sistema é uma estrutura de máquina que consiste em membros multi-força móveis conectados por pinos que formam um sistema estabilizado para transmitir forças.
Aqui, o membro CD é um membro de duas forças. Portanto, as forças colineares que atuam em ambas as extremidades são iguais em magnitude, mas opostas em direção.
Um diagrama de corpo livre para a seção BCF é construído e a condição de equilíbrio de momento é aplicada no pino pivô B. O resultado fornece o valor da força ao longo do membro CD.
Aplicando a condição de equilíbrio de força horizontal, a força de reação horizontal na junta B é obtida.
Agora, considerando um diagrama de corpo livre para a seção EBA, a condição de equilíbrio de momento pode ser aplicada na junta A.
Substituindo o valor da força de reação horizontal em B na equação de equilíbrio de momento, a força que atua na placa de fixação no ponto E é obtida.

<ol>
	<li>Hibbeler, R.C. (2016). Engenharia Mecânica \u2012 Estática e Dinâmica. Hoboken, Nova Jersey: Pearson Prentice Hall. Pág. 305.</li>
	<li>Cerveja, F.P.; Johnston, E.R.; Mazurek, D.F; Cromwell, PJ e Self, BP (2019). Mecânica vetorial para engenheiros \u2012 estática e dinâmica. Nova Iorque: McGraw-Hill. pág. 348</li>
	<li>Meriam, J.L., Kraige, L.G., e Bolton, J.N. (2020). Engenharia Mecânica \u2012 Estática. Hoboken, Nova Jersey: John Wiley. pág. 200</li>
</ol>

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máquinas: resolução de problemas i

Uma braçadeira de alavanca é um dispositivo mecânico comumente usado para segurar e fixar objetos em várias aplicações, como marcenaria, metalurgia e operações de montagem. Considere uma braçadeira de alavanca sujeita a uma força de 200 N na alavanca. A força vertical de fixação pode ser calculada, desde que as dimensões da braçadeira de alavanca sejam conhecidas.

O sistema de braçadeira de alavanca é uma estrutura mecânica composta por membros móveis e conectados por pinos que formam um sistema estabilizado para transmitir forças. O membro CD é um membro de força dupla, o que significa que as forças colineares atuando em ambas as extremidades são iguais em magnitude, mas opostas em direção.

<img alt="Figure 1" src="/files/ftp_upload/14294/14294_PT_Fig_1v2.svg" style="text-align: center; height: 350px;" />

Um diagrama de corpo livre da seção BCF é considerado para analisar as forças. A condição de equilíbrio de momento é aplicada ao pino pivotante B.

<img alt="Equation 1" src="/files/ftp_upload/14294/14294_PT_Equation_1v2.svg" style="text-align: center; height: 13px;" />

O resultado fornece a força ao longo do membro CD como 2185,64 N. Substituindo o valor da força ao longo do membro CD na condição de equilíbrio de força horizontal, a força Bx é calculada como 1092,82 N.

<img alt="Equation 2" src="/files/ftp_upload/14294/14294_PT_Equation_2v2.svg" style="text-align: center; height: 13px;" />

Considerando um diagrama de corpo livre para a seção EBA, a condição de equilíbrio de momento é aplicada na junta A.

<img alt="Equation 3" src="/files/ftp_upload/14294/14294_PT_Equation_3v2.svg" style="text-align: center; height: 13px;" />

Substituindo o valor da força de reação horizontal em B na equação de equilíbrio de momento, o valor da força de fixação vertical no ponto E é calculado como 728,55 N.

Máquinas: Resolução de Problemas I

Um grampo de alternância é um dispositivo mecânico comumente usado para segurar e prender objetos em várias aplicações, como marcenaria, metalurgia e ...

Education

JoVE Core

Mechanical Engineering

Engenharia Mecânica

Unit 1

Unidade 1

Structural Analysis

Análise Estrutural

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

Machines: Problem Solving I

toggle clamp force analysis

A toggle clamp can be analyzed to find its clamping force from a known handle force. In this example, a 200 N force is applied at the handle. The clamp is used in holding and clamping tasks in woodworking, metalworking, and assembly operations.

The toggle clamp is a machine structure made of movable, pin-connected multi-force members. These members form a stabilized system that transmits force. Member CD is a two-force member, which means the forces at its ends are equal in magnitude and opposite in direction.

To solve the force problem, a free-body diagram is drawn for section BCF. The moment equilibrium condition is applied about pivot pin B. This gives the force along member CD as 2185.64 N. That value is then used in the horizontal force equilibrium equation to find the horizontal reaction at B, Bx = 1092.82 N.

A second free-body diagram is then taken for section EBA. The moment equilibrium condition is applied at joint A. Using the horizontal reaction force at B, the vertical clamping force at point E is found to be 728.55 N.

Toggle Clamp Force Analysis

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machines: problem solving i

A toggle clamp can be analyzed to find its clamping force from a known handle force. In this example, a 200 N force is applied at the handle. The clamp is used in holding and clamping tasks in woodworking, metalworking, and assembly operations. The toggle clamp is a machine structure made of movable, pin-connected multi-force members. These members form a stabilized system that transmits force. Member CD is a two-force member, which means the forces at its ends are equal in magnitude and...

machines: problem solving ii

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key terms and concepts

Learn how a toggle clamp uses free-body diagrams and equilibrium equations to turn a 200 N handle force into a 728.55 N clamping force.

Toggle Clamp Force Analysis | JoVE K12

O JoVE Core Mechanical Engineering oferece vídeos animados concisos e de fácil compreensão que abrangem tópicos-chave como equilíbrio, forças, análise de treliças e mecânica estrutural. Explore suas aplicações no mundo real e observe esses conceitos em ação por meio de experimentos conduzidos por cientistas.

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Toggle Clamp Force Analysis

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