Precision 40mm × 88mm Brushless Servo Motor with Encoder – For Robotics, CNC, and Medical Devices

The M40-88-BLDC-E series is a 40mm diameter brushless DC motor with an extended 88mm body length, integrated with a precision encoder for closed-loop speed and position control. This servo-grade motor platform is designed for applications requiring precise motion control without transitioning to larger, more expensive 56mm or 63mm frames. The combination of 40mm diameter and 88mm length provides an excellent power-to-size ratio for robotics, medical devices, and industrial automation applications requiring accurate positioning.

The M40-88 delivers rated torque from 0.25 to 0.50 Nm with peak torque up to 1.2 Nm, depending on winding selection. No-load speeds range from 1,500 to 6,000 RPM, allowing designers to optimize for either high-speed or high-torque applications. The extended 88mm body accommodates a longer stator with more copper windings and stronger rare-earth magnets, resulting in significantly higher torque output compared to shorter 40mm motors (such as 40×60mm versions). The brushless design provides high efficiency (up to 89%), reducing heat generation and improving energy economy.

The integrated encoder is the key feature distinguishing this series from standard brushless motors. Available with optical or magnetic sensing technology, the encoder provides resolutions up to 2,048 pulses per revolution (PPR). The standard optical encoder outputs A, B, and Z (index) channels with RS422 line driver output for noise immunity in industrial environments. For absolute position feedback, a magnetic absolute encoder option is available, eliminating the need for homing on power-up. An optional commutation track (U, V, W) can be integrated into the encoder for sensorless backup or simplified drive configuration.

Unlike traditional metal brush DC motors that require periodic brush replacement and suffer from electrical arcing, the brushless design eliminates mechanical commutation entirely. Typical operational life reaches 20,000+ hours—four to six times longer than equivalent brushed motors. The absence of brushes also eliminates electrical arcing, reducing EMI and making the motor suitable for sensitive medical and electronic environments. Low cogging torque design ensures smooth rotation even at very low speeds, critical for precision positioning applications.

Three integrated hall effect sensors provide commutation feedback as a backup to the encoder, ensuring reliable motor startup and operation even if encoder signals are compromised. The hall sensors also simplify initial drive configuration and tuning. For applications requiring position holding when power is removed, an optional electromagnetic holding brake (fail-safe, 12V/24V) can be added to the motor rear shaft behind the encoder.

The 88mm body length provides ample surface area for passive heat dissipation. Ball bearings (double shielded) on both ends ensure low friction and long service life even under continuous duty. Dynamic balancing of the rotor assembly minimizes vibration, important for precision applications such as CNC axes and surgical robots. The housing can be specified with IP54 protection (dust-protected and water-resistant) or IP65 (wash-down capable) for demanding environments. Insulation is Class F (155°C) as standard, with Class H (180°C) available for high-temperature applications.

OEM customers can specify winding voltage and speed/torque characteristics, shaft diameter (8mm, 10mm, or 12mm), shaft length, and end configurations including flat, keyway, D-cut, or spline. Encoder type and resolution can be selected from multiple options. Custom lead wire length and connector terminations (Molex, JST, AMP, Deutsch, or custom) are supported. Electromagnetic brake integration, IP65 sealing, and special mounting flanges are available for volume orders.

Each M40-88-BLDC-E motor undergoes 100% final inspection including no-load speed, no-load current, hall sensor functionality, encoder signal verification, insulation resistance, dielectric strength, vibration testing, and shaft runout measurement. Production follows ISO 9001:2015 quality management processes. RoHS and REACH compliance documentation is available. Sample motors with matched servo drives are available for engineering evaluation.