Calculated Wear Life
LIFE OF CAM CLUTCH Regarding Cam Clutch life, there are two conditions that have a major impact. These are listed below. When assessing the expected lifetime of the Cam Clutch it is important to consider these in relation to the actual application: 1. Overrunning abrasion (wear) life 2. Engagement fatigue life When assessing the expected lifetime of the Cam Clutch, it is important to consider the above conditions in relation to the actual application.
Outer race
Cam
Inner race
Overrunning abrasion (wear) life *When the Cam Clutch overruns:
On the contact surfaces of cams and races, skids occur in direct proportion to the overrunning rotational speed. Therefore it is important to pay particular attention to abrasions at the contact points. As the contact pressure by the weak spring force F is low, with sufficient lubrication, these parts will not wear or abrade in a short time. Though it may vary depending on the lubricating condition, the right graph shows the calculated abrasion life, which has been properly lubricated based on the instructions provided in the catalog. Abrasion life must be verified especially for applications involving high speed and long overrunning periods.
Variable Load Torque Graph Time Variable Load Torque Graph
Engagement fatigue life *When the Cam Clutch engages:
At the contact surfaces of cams and races, the compression stress occurs in direct proportion to engagement torque. Contact surface of inner/ outer races move infinitely with respect to each engagement, while that of the cams are almost stable. Therefore, the fatigue caused by this stress will then result in the surface pitting of cams. Refer to the fatigue life curve, and check the expected life.
Outer race
Cam
Oil lm
Inner race
Note: In cases where the load applied to the Cam Clutch changes, or where
vibrational loads are encountered, repeated torque loads can be applied during a single clutch engagement. The Variable Load Torque Graph shows the type of repetitive torque loads which can be applied to the Cam Clutch in these cases. Repeated torque loads during a single clutch engagement can have the effect of increasing the overall torque load, and this must also be considered when determining Cam Clutch service life.
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