Adept Python - Manual (Page 38)

Chapter 3 - Python Linear Module Descriptions
38 Adept Python Modules User’s Guide, Rev. E
L-Series Module Types
Three Python L-Series linear module types are available: L18, L12, and L08. All three
module types have similar construction features:
• Rigid aluminum extruded-frame bodies for high stiffness with
precision-machined straightness tolerances
• Dual linear square rails with four preloaded bearings per carriage to maximize
carriage stiffness and assure high moment load capacities
• Precision ground screw, low backlash ball screw drivetrain (rolled screws used on
certain module configurations)
• Maintenance-free operation - all bearing components are lubricated for life
• High-performance AC servo motors with 8 kHz servo update rate and optimized
current loop tuning in amplifier
• Serial absolute encoders with 65,536 counts/rev minimum resolution; no homing
required
• Zero-backlash, high-stiffness shaft couplings
• Extruded covers with integral belt seals to keep dust out and provide IP-20 ingress
protection
• Mounting options including bolt and dowel pin patterns on underside and
extruded T-slots for toe clamp mounting
All external dimension and weight specifications for each module type can be found on
the module specification drawings located on the Adept website. The load ratings for each
module type scale with the frame size and ball screw lead.
Payloads and Moments
For cantilevered or simply-supported applications, the stiffness of the module's main
body extrusion is an important parameter to determine overall system and tool tip
stiffness. The Python modules main body moment of inertia and polar moment of inertia
values, listed in the following table, can be used to calculate approximate system tool tip
stiffness.
Python linear modules employ high quality linear rails manufactured by IKO corporation.
The following load rating values and maximum transportable moments apply to the
carriage bearing life. These values are typically motor and/or ball screw dependent.
Table 3-1. Main Body Extrusion Moment of Inertia
Module Type IXX (Pitch) IYY (Yaw) Polar (Roll) Units
L18 8.74E+5 2.37E+7 3.31E+7 mm 4
L12 5.47E+5 5.64E+6 6.95E+6 mm 4
L08 3.20E+5 1.56E+6 2.20E+6 mm 4