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3-3. Relationship between gripping part center height, static
griping force and input force / Relationship between top jaw
mass moment and gripping force loss
If the gripping part center height of the used top jaw (dimension H in Fig. 7) is higher than
the gripping part center height of the standard soft jaw, a large load is applied to the master
jaw, T nut, jaw attaching bolts, etc. To prevent these parts from being broken, it is necessary
to use the machine by using a lower input force than the allowable maximum input force.
Additionally, if the top jaw is larger and heavier, the centrifugal force generated at the top
jaw will increase. It is necessary to examine the dynamic gripping force considering the
centrifugal force and to use the machine at a rotation speed that can withstand the cutting
force.
G: Center of mass of the top jaw
m: Mass of the top jaw
r: Distance from the center of mass of the top jaw to the chuck center
H: Gripping center height
Fig.7
・
Keep the height of the top jaw within the range of the gripping force limit table.
(Refer to Fig.8)
・
If a top jaw is taller than the standard soft jaw, use it at the input force (piston
thrust force, draw pipe drawing force) specified in the gripping force limit
table. If it is used without lowering the input, the chuck will break and this is
dangerous as the chuck and work will fly out.
Summary of Contents for QB300
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