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

Si consideri un morsetto a ginocchiera sottoposto a una forza di 200 Newton sull'impugnatura.
Qual è la forza di serraggio verticale, a condizione che le dimensioni del morsetto a ginocchiera siano note?
Questo sistema è una struttura della macchina costituita da elementi multiforza mobili e collegati a perni che formano un sistema stabilizzato per trasmettere le forze.
Qui, il membro CD è un membro a due forze. Quindi le forze collineari che agiscono ad entrambe le estremità sono uguali in grandezza ma opposte in direzione.
Viene costruito un diagramma di corpo libero per la sezione BCF e la condizione di equilibrio del momento viene applicata al perno di articolazione B. Il risultato fornisce il valore della forza lungo l'asta CD.
Applicando la condizione di equilibrio della forza orizzontale, si ottiene la forza di reazione orizzontale al giunto B.
Ora, considerando un diagramma di corpo libero per la sezione EBA, la condizione di equilibrio del momento può essere applicata al giunto A.
Sostituendo il valore della forza di reazione orizzontale in B nell'equazione del momento di equilibrio, si ottiene la forza che agisce sulla piastra di serraggio nel punto E.

<ol>
	<li>Hibbeler, R.C. (2016). Ingegneria Meccanica \u2012 Statica e Dinamica. Hoboken, New Jersey: Pearson Prentice Hall. Pagine 305.</li>
	<li>Birra, F.P.; Johnston, E.R.; Mazurek, D.F; Cromwell, P.J. e Self, B.P. (2019). Meccanica vettoriale per ingegneri \u2012 Statica e dinamica. New York: McGraw-Hill. pagine 348</li>
	<li>Meriam, JL, Kraige, LG e Bolton, JN (2020). Ingegneria Meccanica \u2012 Statica. Hoboken, New Jersey: John Wiley. pagine 200</li>
</ol>

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macchine: risoluzione dei problemi i

Una pinza a leva è un dispositivo meccanico comunemente usato per tenere e bloccare oggetti in diverse applicazioni, come in falegnameria, nella lavorazione dei metalli e in operazioni di assemblaggio. Consideriamo una pinza a leva sottoposta a una forza di 200 N sulla maniglia. La forza di bloccaggio verticale può essere calcolata, a condizione che siano noti le dimensioni della pinza.

Il sistema della pinza a leva è una struttura macchinale composta da membri mobili collegati da cerniere che formano un sistema stabilizzato per trasmettere forze. Il membro CD è un membro a due forze, il che significa che le forze collineari che agiscono su entrambe le estremità, sono uguali in magnitudine ma opposte in direzione.

<img alt="Figure 1" src="/files/ftp_upload/14294/14294_PT_Fig_1v2.svg" style="text-align: center; height: 350px;" />

Viene considerato un diagramma di corpo libero per la sezione BCF per analizzarne le forze. Viene applicata la condizione di equilibrio dei momenti al perno di rotazione B.

<img alt="Equation 1" src="/files/ftp_upload/14294/14294_PT_Equation_1v2.svg" style="text-align: center; height: 13px;" />

Il risultato fornisce la forza lungo il membro CD pari a 2185.64 N. Sostituendo il valore della forza lungo il membro CD nella condizione di equilibrio delle forze orizzontali, la forza Bx viene calcolata di 1092.82 N.

<img alt="Equation 2" src="/files/ftp_upload/14294/14294_PT_Equation_2v2.svg" style="text-align: center; height: 13px;" />

Considerando un diagramma di corpo libero per la sezione EBA, viene applicata la condizione di equilibrio dei momenti all'articolazione A.

<img alt="Equation 3" src="/files/ftp_upload/14294/14294_PT_Equation_3v2.svg" style="text-align: center; height: 13px;" />

Sostituendo il valore della forza di reazione orizzontale in B nell'equazione di equilibrio dei momenti, viene calcolato il valore della forza di bloccaggio verticale al punto E pari a 728.55 N.

Macchine: Risoluzione dei problemi I

Un morsetto a ginocchiera è un dispositivo meccanico comunemente utilizzato per tenere e bloccare oggetti in varie applicazioni, come la lavorazione del legno, la lavorazione dei metalli e ...

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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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