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

Stellen Sie sich einen Schnellspanner vor, der einer Kraft von 200 Newton am Griff ausgesetzt ist.
Wie hoch ist die vertikale Spannkraft, sofern die Abmessungen des Schnellspanners bekannt sind?
Bei diesem System handelt es sich um eine Maschinenstruktur, die aus beweglichen, mit Stiften verbundenen Multikraftelementen besteht, die ein stabilisiertes System zur Kraftübertragung bilden.
Hier ist das Mitglied CD ein Zwei-Kräfte-Mitglied. Die kollinearen Kräfte, die an beiden Enden wirken, sind also gleich groß, aber in entgegengesetzter Richtung.
Es wird ein Freikörperdiagramm für den Schnitt BCF erstellt, und die Momentengleichgewichtsbedingung wird am Drehzapfen B angewendet. Das Ergebnis ergibt den Wert der Kraft entlang des Stabes CD.
Unter Anwendung der horizontalen Kraftgleichgewichtsbedingung erhält man die horizontale Reaktionskraft am Gelenk B.
Unter Berücksichtigung eines Freikörperdiagramms für den Schnitt EBA kann nun die Momentengleichgewichtsbedingung an Gelenk A angewendet werden.
Setzt man den Wert der horizontalen Reaktionskraft bei B in die Momentengleichgewichtsgleichung ein, erhält man die Kraft, die am Punkt E auf die Klemmplatte wirkt.

<ol>
	<li>Hibbeler, R.C. (2016). Technische Mechanik \u2012 Statik und Dynamik. Hoboken, New Jersey: Pearson Prentice Hall. Seite 305.</li>
	<li>Bier, F.P.; Johnston, E.R.; Mazurek, D.F.; Cromwell, P.J. und Self, B.P. (2019). Vektormechanik für Ingenieure \u2012 Statik und Dynamik. New York: McGraw-Hill. Seite 348</li>
	<li>Meriam, J.L., Kraige, L.G. und Bolton, J.N. (2020). Technische Mechanik \u2012 Statik. Hoboken, New Jersey: John Wiley. Seite 200</li>
</ol>

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maschinen: problembehebung i

Ein Kniehebelspanner ist ein mechanisches Gerät, das häufig zum Halten und Klemmen von Objekten in verschiedenen Anwendungen verwendet wird, wie z.B. Holzbearbeitung, Metallbearbeitung und Montagearbeiten. Betrachten wir einen Kniehebelspanner, der einer Kraft von 200 N am Griff ausgesetzt ist. Die vertikale Spannkraft kann berechnet werden, vorausgesetzt, die Abmessungen des Kniehebelspanners sind bekannt. Das Kniehebelspannersystem ist eine Maschinenstruktur, die aus beweglichen, über Stifte verbundenen Mehfachkraftgliedern besteht, die ein stabilisiertes System zur Kraftübertragung bilden. Das Glied CD ist ein Zweikraftglied, was bedeutet, dass die kollinearen Kräfte, die an beiden Enden wirken, sowohl in der Größe als auch in der Richtung entgegengesetzt sind. <img alt="Figure 1" src="/files/ftp_upload/14294/14294_PT_Fig_1v2.svg" style="text-align: center; height: 350px;"> Eine Freikörperdiagramm für den Abschnitt BCF wird betrachtet, um die Kräfte zu analysieren. Die Gleichgewichtsbedingung des Moments wird auf den Stift D angewendet. <img alt="Equation 1" src="/files/ftp_upload/14294/14294_PT_Equation_1v2.svg" style="text-align: center; height: 13px;"> Das Ergebnis ergibt die Kraft entlang des Glieds CD als 2185,64 N. Durch das Einsetzen des Wertes der Kraft entlang des Glieds CD in die Gleichgewichtsbedingung der Horizontalen wird die Kraft Bx als 1092,82 N berechnet. <img alt="Equation 2" src="/files/ftp_upload/14294/14294_PT_Equation_2v2.svg" style="text-align: center; height: 13px;"> Bei Betrachtung eines Freikörperdiagramms für den Abschnitt EBA wird die Gleichgewichtsbedingung des Moments am Gelenk A angewendet. <img alt="Equation 3" src="/files/ftp_upload/14294/14294_PT_Equation_3v2.svg" style="text-align: center; height: 13px;"> Durch das Einsetzen des Wertes der horizontalen Reaktionskraft an B in die Momentgleichgewichtsgleichung wird der Wert der vertikalen Spannkraft am Punkt E auf 728,55 N berechnet.

Maschinen: Problembehebung I

Ein Schnellspanner ist eine mechanische Vorrichtung, die häufig zum Halten und Spannen von Gegenständen in verschiedenen Anwendungen verwendet wird, wie z. B. in der Holzbearbeitung, Metallbearbeitung und ...

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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

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.

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Toggle Clamp Force Analysis

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