Name: friction torque in collar bearings
Uploaded: 2023-09-22T11:49:30.000Z
Duration: 1 min 23 s
Channel: JoVE

Bundlager sind eine Art von Lagern, die in Maschinen verwendet werden, um axiale Lasten auf rotierenden Wellen aufzunehmen, sie können einzelne oder mehrere Ringe haben.
Stellen Sie sich ein einzelnes Bundlager vor, das einer axialen Belastung ausgesetzt ist. Die Fläche zwischen dem Außen- und dem Innenradius des Kragens ist die gesamte Lagerkontaktfläche.
Unter der Annahme einer gleichmäßigen Abstützung des Lagers kann der gleichmäßige Normaldruck als Verhältnis der Kraft über den Lagerbereich ausgedrückt werden.
Betrachten Sie ein infinitesimales Flächenelement auf dem Lager. Die Kraft, die auf die Differenzfläche wirkt, kann als Produkt aus dem Reibungskoeffizienten, dem Druck und der Differenzfläche ausgedrückt werden.
Das Moment, das erforderlich ist, um eine bevorstehende Drehung der Welle zu verursachen, wird aus der Momentengleichgewichtsgleichung um die Rotationsachse bestimmt.
Als nächstes wird die Integration verwendet, um das aufgewendete Moment zu bestimmen, das zur Überwindung aller Reibungskräfte erforderlich ist.
Schließlich kann durch Einsetzen der Werte der Differenzkraft und der Differenzfläche und der Integration der Gleichung über die gesamte Lagerfläche das Moment der Welle geschätzt werden.

<ol>
	<li>Hibbeler, R.C. (2016). Technische Mechanik \u2012 Statik und Dynamik. Hoboken, New Jersey: Pearson Prentice Hall. Seiten 447-448.</li>
</ol>

kragenlager

Kragenlager sind in verschiedenen Maschinen unerlässlich, die dazu dienen, axiale Lasten auf drehenden Wellen zu unterstützen. Je nach spezifischer Anwendung und Anforderungen können sie mit einem oder mehreren Kragen gefunden werden. <img alt="Figure 1" src="/files/ftp_upload/14325/14325_Figure_1v3.svg" style="text-align: center; height: 300px;"> Betrachten wir ein einzelnes Kragenlager, das einer axialen Belastung ausgesetzt ist. Die gesamte Lagerkontaktfläche ist der Bereich zwischen dem äußeren Radius und dem inneren Radius des Kragens. Wenn angenommen wird, dass das Lager eine gleichmäßige Unterstützung bietet, kann der gleichmäßige Normalkontakt durch die Division der auf den Kragen ausgeübten Kraft durch die gesamte Lagerkontaktfläche berechnet werden. Dieser Wert stellt die durchschnittliche Druckverteilung über die Lageroberfläche dar. Um die auf das Kragenlager wirkenden Kräfte weiter zu analysieren, betrachten wir ein kleines, infinitesimales Flächenelement auf der Lageroberfläche. Die auf diesem infinitesimalen Bereich wirkende Kraft ist das Produkt aus Reibungskoeffizient, Druck und differentieller Fläche. Das Verständnis des Zusammenhangs zwischen diesen Variablen ist entscheidend für die Berechnung des für die Wellenrotation erforderlichen Moments. Die bevorstehende Rotation der Welle wird durch die Analyse der Momentengleichgewichtsgleichung um die Rotationsachse bestimmt. Diese Gleichung berücksichtigt alle auf die Welle wirkenden Kräfte und Momente, einschließlich der durch das Kragenlager erzeugten Reibungskräfte. <img alt="Equation 1" src="/files/ftp_upload/14325/14325_Equation_1v2.svg" style="text-align: center; height: 39px;"> Durch Integration der Gleichung kann das benötigte Moment, um diese Reibungskräfte zu überwinden und die Wellenrotation einzuleiten, bestimmt werden. Schließlich können die differentiellen Kraft- und Flächenwerte in die integrierte Gleichung eingesetzt werden, um das Moment der Welle abzuschätzen. <img alt="Equation 2" src="/files/ftp_upload/14325/14325_Equation_2v2.svg" style="text-align: center; height: 55px;"> Die Integration dieser Gleichung über die gesamte Lagerfläche ermöglicht ein umfassendes Verständnis der auf das Kragenlager wirkenden Kräfte und Momente sowie des für die Wellenrotation erforderlichen Moments. <img alt="Equation 3" src="/files/ftp_upload/14325/14325_Equation_3v2.svg" style="text-align: center; height: 39px;">

Kragenlager

Bundlager sind in verschiedenen Maschinen unerlässlich, die für die Aufnahme von Axiallasten auf rotierenden Wellen ausgelegt sind. Abhängig von der spezifischen Anwendung und ...

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Collar Bearings

friction torque in collar bearings

Collar bearings support axial loads on rotating shafts, and their friction helps determine the torque needed to start motion. They are used in many machines and may have a single collar or multiple collars, depending on the application and load needs.

For a single collar bearing under an axial load, the contact area is the ring-shaped region between the external radius and the internal radius of the collar. If the bearing is assumed to support the load evenly, the uniform normal pressure is found by dividing the applied force by this total bearing contact area. This gives the average pressure across the bearing surface.

To study the forces more closely, a small infinitesimal area element is considered on the collar surface. The force on that tiny area equals the friction coefficient times the pressure times the differential area. Using this relationship is important for finding the moment required to rotate the shaft.

The impending rotation of the shaft is found by writing the moment equilibrium equation about the rotational axis. This equation includes the forces and moments on the shaft, along with the frictional forces from the collar bearing. When the equation is integrated over the full bearing area, the applied moment needed to overcome friction and begin rotation can be determined.

Friction Torque in Collar Bearings

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collar bearings

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key terms and concepts

Learn how collar bearing contact area, pressure, and friction work together to set the torque needed to start shaft rotation in mechanical systems.

Friction Torque in Collar Bearings | JoVE K12

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mechanical engineering

Friction Torque in Collar Bearings

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