FHA-C Series - Harmonic Drive LLC

Chapter 2 Guidelines for sizing2-4 Duty cyclesWhen a duty cycle includes many frequent start and stop operations,the actuator generates heat by high starting and braking current.Therefore, it is necessary to study the duty cycle profile.Screw pitch (mm)30Speed (r/min)The study is as follows:2-4-1 Actuator speedCalculate the required actuator speed (r/min) to drive the load.For linear motion, convert with the formula below:Linear speed (mm/min)Rotary speed (r/min) = (9)Pitch of screw (mm)Select a reduction ratio from [50], [100] and [160] of an actuatorof which the maximum speed is more than the required speed.10335r/min50r/min70r/min100r/min130 100 300 1000 3000Li near speed (mm/min)20r/min2-4-2 Load inertiaCalculate the load inertia driven by the FHA-C series actuator.Refer to appendix 1 for the calculation.Tentatively select an FHA-C actuator referring to section[2-1 allowable load inertia] with the calculated value.2-4-3 Load torqueCalculate the load torque as follows:• Rotary motionThe torque for the rotating mass [W] on the friction ring of radius [r]as shown in the figure to the right.Friction:Mass: WRadius:rT = 9.8 x µ x W x rT: torque (N•m)µ : coefficient of frictionW: mass (kg)r: radius of friction face (m)300Ex. torque calculation (friction=0.1)FHA : (ratio: 1/50) 30% torque of maximum torque10 N•m7 N•m5 N•m20 N•m 50 N •m 100 N•m 200 N•m30 N•m300 N•m1003 N•mIn the right graph, the oblique solid linesfor torque have been calculated with thecoefficient of the friction of µ=0.1.The oblique dot-chain lines show20% torque of actuators converted from300% torque corresponding to its maximum torque.30102 N•m1 N•mFHA- 17C-50FHA- 40C-50FHA-32C-50FHA-25C-5030 100 300 1000 3000Mass: W (k g)Harmonic Drive LLC 800-921-333224