Product Description:

The SF-B4.0125.060-10.000 is a brushless AC servo motor produced by Bosch Rexroth Indramat as part of the SF Servo Motors series. It is designed for precision motion tasks in industrial automation, providing controlled torque and speed to ball screws, timing belts, or direct-drive rotary tables through a smooth shaft. Integrated electronic commutation and digital feedback allow the connected drive controller to maintain tight position loops during fast cycles. The motor is suited for servo-controlled axes that require repeatable starts, stops, and speed changes under varying load conditions.

At the electrical level, the motor develops a rated mechanical speed of 6000 rpm, giving adequate headroom for high-speed indexing when combined with gear reduction or direct coupling. The electromagnetic design yields a torque constant of 0.71 Nm/A, so output torque rises predictably with commanded phase current. Under locked-rotor conditions, the winding draws 17 A and produces a stall torque of 12 Nm, which helps establish current demand during peak loading. Position feedback comes from an STG encoder that provides 8 million incr./rev, supporting very fine command interpolation and smooth low-speed regulation. The motor body length of 277 mm balances copper fill with cooling surface, and the Ø24 × 50 mm smooth shaft supports backlash-free clamp couplings.

In mechanical integration, the square mounting interface uses a 142 mm flange, allowing installation on machine faces with the same bolt circle. Total reflected inertia, including the encoder, is 30 × 10⁻⁴ kg·m², reducing the load on the drive during acceleration while still helping stabilize lightweight linkages. The motor has a mass of 16 kg, which should be considered when the axis structure supports the unit in an overhung position. The feedback system reports position with an accuracy of ±20 arcsec, keeping closed-loop error low in electronic assembly and optical equipment. This level of precision supports applications where small angular deviations can affect alignment during motion.