The SKR-type LM guide actuator with Caged Ball Technology is a compact actuator that places a nut block(s) that integrates an LM block and ball screw nut onto the inside of the LM rail of a U-shaped cross-sectional form.
Moreover, the addition of the LM guide and ball screw sections with Caged Ball Technology allows the SKR-type LM guide actuator to achieve higher speed, lower noise, longer maintenance-free operation, and other features in comparison with the conventional KR-type.
Features of the Model SKR:
Four-way Equal Load Rating
Each
row of balls is arranged at a contact angle of 45‚° so that loads acting
on the nut block in the four directions (radial, reverse-radial, and
two lateral directions) show the same rated load. Thus, the SKR-type LM
guide actuators can be used in any position.
High Rigidity
The adoption of the LM rail of a U-shaped cross-sectional form allows improved rigidity against moment.
High Precision
The
linear motion guide raceway has four rows of circular arc grooves that
provide smooth motion by mere pre-load; clearance-free, highly rigid
guidance is obtained. In addition, changes in frictional resistance
resulting from load variations are minimized, allowing the SKR-type to
achieve high-precision feed.
Space Saving
The
integration of a LM guide raceway on both side faces of a nut block and
the integration of a ball screw nut at the center of the nut block
allow the SKR-type to achieve high rigidity and high precision in a
minimal space.
Long Life Span and Long-term Maintenance-free Operation
Thanks
to the effectiveness of its ball retainers, the SKR has improved grease
retention capability, allowing it to achieve a long life span and
long-term maintenance-free operation. The SKR achieves a longer life
span because its basic dynamic rated load at the LM guide and ball
screw sections is greater than that of the conventional KR models (in
the case of the KR3310, three times greater). The rated life span can
be calculated by the following equation.
High Speed
Through
the use of Caged Ball Technology, the SKR-type is compatible with the
latest high-speed rotational AC servo-motors (6000 min-1), achieving
higher speeds than the conventional KR-type. The ball screw lead
settings of the conventional KR33 type were 6 mm and 10 mm. To achieve
a higher feed rate, a 20 mm ball screw lead has been added to the new
SKR 33 series.
Excellent Sliding Capability
Caged
Ball Technology also helps the SKR-type eliminate ball-to-ball
friction, significantly improving the torque characteristics. It
minimizes torque variations, allowing excellent sliding capability.
Low Noise
The
use of Caged Ball Technology in the LM guide and ball screw allows the
SKR-type to eliminate the noise caused by the balls colliding. This
lets the SKR-type achieve low noise emission and a pleasing sound
quality.
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::Design World::
Filed Under: Actuators, Motion control • motor controls