Driving forces up to 30N
20 mK to 375K, vacuum compatible
Full ceramic spindle and nut, uncoated
Extreme stability due to self locking nature
No power dissipation when “off”
Robust design for easy handling
High drive stiffness
Cryo Optical Encoder option “COE”
The Cryo Linear Actuator (CLA) or “Piezoknob” is developed for nanometric positioning in a cryo-vacuum environment. Piezo ceramics in the disc-shaped head generate torque pulses which cause the spindle to rotate relative to the stationary nut yielding linear motion. Both spindle and nut are ceramic and run without coatings which could be worn off due to extensive use. Due to its self-locking nature stability in the sub-nanometer range is obtained. The result is an actuator ideally suited for set and forget applications with nanometric step size and driving forces of tens of Newtons.
|Type of motion||-||x|
|Min. step size @ ambient||nm||5|
|Min. step size @ 4K||nm||1|
|Max. velocity @ ambient||µm/s||25|
|Max. velocity @ 4K||µm/s||15|
|Min. required preload||N||3|
|Max. driving force @4K||N||20||20||30||30|
|Operating voltage||V||-20 … +130|
|Main construction material||-||Stainless steel 316L, ceramic, aluminium (COE)|
|Dissipation @ ambient||mJ/step||0.59|
|Dissipation @ 4K||mJ/step||0.055|
|Encoder resolution *||PPR||N/A||710||N/A||850|
|Controller/driver||-||CAB-230(115), CADM(2), MCM|
|* Linear resolution can be found by dividing the spindle pitch by PPR (pulses per revolution)|
The objective is to reposition the moving mass from p0 to p2. In the initial condition a steady-state voltage is applied to the piezo and a normal force F is applied to the moving mass to generate friction.
Slowly decreasing the voltage shortens the piezo and the inertial mass is ‘pulled’ to position x1 . The moving mass remains on its initial position (p1 = p0) due to the friction.
Now, the voltage is rapidly increased to expand the Piezo to its original length. This rapid expansion accelerates the inertial mass and the resulting force on the moving mass overcomes the friction, causing a shift to position p2. Because the inertial mass is larger (more inertia) it will move less backwards than the moving mass shifts forward. After this step the system is in steady state again, at position p2, ready for the next step.
CLA2201 Cryo Linear Actuator size 22
CLA2201-COE CLA2201 incl. Cryo Optical Encoder
CLA2601 Cryo Linear Actuator size 26
CLA2601-COE CLA2601 incl.Cryo Optical Encoder