Electric Rotary Table Series LER Model Selection Step Motor (Servo/24 VDC) H a b Selection Procedure Electric rotary table: LER30J Mounting position: Horizontal Load type: Inertial load Ta Configuration of load: 150 mm x 80 mm (Rectangular plate) Rotation angle θ: 180° Angular acceleration/ angular deceleration ω ・ : 1,000°/sec2 Angular speed ω: 420°/sec Load mass m: 2.0 kg Distance between shaft and center of gravity H: 40 mm Operating conditions Moment of inertia.Angular acceleration/deceleration Necessary torque Allowable load Rotation time Step 1 Step 2 Step 3 Step 4 qCalculate the moment of inertia Formula = m x (a2 + b2)/12 + m x H2 Selection example = 2.0 x (0.152 + 0.082)/12 + 2.0 x 0.042 = 0.00802 kg・m2 LER30 0.000 0.005 0.010 0.015 0.020 0.025 0.030 100 1000 10000 Angular acceleration/angular deceleration: ω ・ (°/s2) Moment of inertia: Ι (kg・m2) LER�ｭ30K High torque LER�ｭ30J Basic w Check the moment of inertia.angular acceleration/deceleration Select the target model based on the moment of inertia and angular acceleration and deceleration with reference to the (Moment of Inertia.Angular Acceleration/ Deceleration graph). I I qLoad type . Static load: Ts . Resistance load: Tf . Inertial load: Ta Formula Effective torque . Ts Effective torque . Tf x 1.5 Effective torque . Ta x 1.5 Selection example Inertial load: Ta Ta x 1.5 = x ω ・ x 2 π/360 x 1.5 = 0.00802 x 1,000 x 0.0175 x 1.5 = 0.21 N・m LER30 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 0 100 200 300 400 500 Angular speed: ω (°/s) Effective torque: T (N・m) LER�ｭ30K High torque LER�ｭ30J Basic wCheck the effective torque Confirm whether it is possible to control the speed based on the effective torque corresponding with the angular speed with reference to the (Effective Torque. Angular Speed graph). I qCheck the allowable load . Radial load . Thrust load . Moment Formula Allowable thrust load . m x 9.8 Allowable moment . m x 9.8 x H Selection example �慎hrust load 2.0 x 9.8 = 19.6 N < Allowable load OK �植llowable moment 2.0 x 9.8 x 0.04 = 0.784 N・m < Allowable moment OK qCalculate the cycle time (rotation time) T1 ω・ 1 ω・ 2 θ Speed: ω [°/sec] Time [s] T2 T3 T4 θ: Rotation angle [°] ω: Angular speed [°/sec] ω・ 1: Angular acceleration [°/sec2] ω・ 2: Angular deceleration [°/sec2] T1: Acceleration time [s]…Time until reaching the set speed T2: Constant speed time [s] …Time while the actuator is operating at a constant speed T3: Deceleration time [s] …Time from constant speed operation to stop T4: Settling time [s]…Time until in position is completed Formula Angular acceleration time T1 = ω/ω ・ 1 Angular deceleration time T3 = ω/ω ・ 2 Constant speed time T2 = {θ . 0.5 x ω x (T1 + T3)}/ω Settling time T4 = 0.2 (sec) Cycle time T = T1 + T2 + T3 + T4 Selection example �植ngular acceleration time T1 = 420/1,000 = 0.42 sec �植ngular deceleration time T3 = 420/1,000 = 0.42 sec �燭onstant speed time T2 = {180 . 0.5 x 420 x (0.42 + 0.42)}/420 = 0.009 sec �燭ycle time T = T1 + T2 + T3 + T4 = 0.42 + 0.009 + 0.42 + 0.2 = 1.049 (sec) 1