Part i - spindle facts

HSK Clamping - Principle of force amplification
The geometry of grippers and clamping
tapers amplify the pull force. Therefore,
high forces occur mainly in the front part of
the spindle. The patented HSK-clamping
unit offers safety, high pull force and high
life expectancy. The axial stroke is
converted into a radial/axial movement of
the clamping cone towards the gripper
segments. This enables the amplification of
the spring force. The gripper unit moves
parallel, increasing surface contact and
constant amplification of the pull force.
HSK advantage
Figure 41. Principle of force amplification
The HSK-interface shows significant advantages in precision and stiffness compared to the steep
taper interface.
• Higher positional accuracy of the tool due to axial face and taper positions
• Ideal for high speed machining. Easy tool handling due to low weight and dimensions of
the short tapers.
• Heavy duty chip removal can be achieved through total stiffness of the interface, high
pull forces and the resulting transmittable torque.
The automatic interface HSK 25 - HSK 160 are
available in 4 forms:
• Form A is the most common tool standard
with internal drive keys
• Form B has external drive keys, a larger
flange diameter, and is used mainly for
heavy duty chip removal
• Form E without drive keys is used for high
speed operations
Form F has no sealing against coolant and is used
mainly in the woodworking and the plastic
industry.
Over the past years, thousands of employed HSK
units became known for their reliability, long tool
life and high precision. Especially the parallel
moving gripper segments ensure uniform force
amplification and subsequently a 100% reliability
of the interface. The spring in the spacer enables
the gripper segments to hold tools changed with
Figure 42. HSK Clamping Unit
radial offset clamping units and the necessary
contour guarantee perfect sealing of the inside spindle intensifier against dust and coolant.
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