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

Considérons une sauterelle soumise à une force de 200 Newton au niveau de la poignée.
Quelle est la force de serrage verticale, à condition que les dimensions de la sauterelle soient connues ?
Ce système est une structure de machine composée d’éléments multiforces mobiles et reliés par des broches qui forment un système stabilisé pour transmettre les forces.
Ici, le membre CD est un membre à deux forces. Ainsi, les forces colinéaires agissant aux deux extrémités sont égales en amplitude mais opposées en direction.
Un diagramme à corps libre pour la section BCF est construit, et la condition d’équilibre de moment est appliquée à l’axe de pivot B. Le résultat donne la valeur de la force le long de la barre CD.
En appliquant la condition d’équilibre de la force horizontale, la force de réaction horizontale à l’articulation B est obtenue.
Maintenant, si l’on considère un schéma à corps libre pour la section EBA, la condition d’équilibre du moment peut être appliquée à l’articulation A.
En substituant la valeur de la force de réaction horizontale en B dans l’équation d’équilibre du moment, on obtient la force agissant sur la plaque de serrage au point E.

<ol>
	<li>Hibbeler, R.C. (2016). Génie mécanique \u2012 Statique et dynamique. Hoboken, New Jersey : Pearson Prentice Hall. Pages 305.</li>
	<li>Bière, F.P. ; Johnston, E.R. ; Mazurek, D.F ; Cromwell, P.J. et Self, B.P. (2019). Mécanique vectorielle pour les ingénieurs \u2012 Statique et dynamique. New York : McGraw-Hill. p. 348</li>
	<li>Meriam, J.L., Kraige, L.G. et Bolton, J.N. (2020). Génie mécanique \u2012 Statique. Hoboken, New Jersey : John Wiley. page 200</li>
</ol>

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machines : résolution de problèmes i

Un serre-joint à bascule est un dispositif mécanique couramment utilisé pour tenir et serrer des objets dans diverses applications, telles que le travail du bois, le travail des métaux et les opérations d'assemblage. Considérons un serre-joint à bascule soumis à une force de 200 N au niveau de la poignée. La force de serrage verticale peut être calculée, à condition que les dimensions du serre-joint à bascule soient connues. Le système de serre-joint à bascule est une structure de machine composée de membres mobiles reliés par des axes qui forment un système stabilisé pour transmettre des forces. Le membre CD est un membre à deux forces, ce qui signifie que les forces colinéaires agissant aux deux extrémités sont égales en magnitude mais opposées en direction. <img alt="Figure 1" src="/files/ftp_upload/14294/14294_PT_Fig_1v2.svg" style="text-align: center; height: 350px;"> Un diagramme de corps libre pour la section BCF est considéré pour analyser les forces. La condition d'équilibre des moments est appliquée à l'axe de pivot B. <img alt="Equation 1" src="/files/ftp_upload/14294/14294_PT_Equation_1v2.svg" style="text-align: center; height: 13px;"> Le résultat donne la force le long du membre CD comme étant de 2185,64 N. En substituant la valeur de la force le long du membre CD dans la condition d'équilibre des forces horizontales, la force Bx est calculée comme étant de 1092,82 N. <img alt="Equation 2" src="/files/ftp_upload/14294/14294_PT_Equation_2v2.svg" style="text-align: center; height: 13px;"> En considérant un diagramme de corps libre pour la section EBA, la condition d'équilibre des moments est appliquée au joint A. <img alt="Equation 3" src="/files/ftp_upload/14294/14294_PT_Equation_3v2.svg" style="text-align: center; height: 13px;"> En substituant la valeur de la force de réaction horizontale au point B dans l'équation d'équilibre des moments, la valeur de la force de serrage verticale au point E est calculée à 728,55 N.

Machines : Résolution de problèmes I

Une sauterelle est un dispositif mécanique couramment utilisé pour tenir et serrer des objets dans diverses applications, telles que le travail du bois, du métal et ...

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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...

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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

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Toggle Clamp Force Analysis

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