The M40-70 series is a 40mm diameter metal brush DC motor with an extended 70mm body length, representing a significant step up in power from smaller 32mm and 36mm frame motors. This motor platform is designed for applications requiring substantial torque output without transitioning to larger, more expensive 56mm or 63mm frames. The combination of 40mm diameter and 70mm length provides an excellent power-to-size ratio for power tools, industrial equipment, medical devices, and household appliances.
The M40-70 delivers stall torque up to 600 mNm, approximately 70% higher than a typical 32×60mm motor and 40% higher than a 36×60mm motor. No-load speeds range from 1,200 to 8,000 RPM depending on winding selection, allowing designers to optimize for either high-speed or high-torque applications. The metal brush commutation system uses large-format carbon-copper brushes that provide reliable electrical contact under high current loads. Starting torque is exceptionally high, enabling direct drive of mechanisms that would require gearing with smaller motors.
The extended 70mm body length provides substantial surface area for passive heat dissipation, essential for power tools and industrial applications where continuous operation is common. Ball bearings are available as standard on both ends (or sintered bronze for cost-sensitive applications), providing low friction, high radial load capacity, and extended service life. Ventilation slots can be added to the housing for forced air cooling. Insulation is Class B (130°C) as standard, with Class F (155°C) available for high-temperature environments.
The M40-70 features a precision-drawn or machined steel housing with integrated mounting bosses. The commutator is precision diamond-turned for smooth brush interaction, minimizing sparking and extending brush life beyond 3,000 hours under typical loads. Dynamic balancing of the rotor assembly reduces vibration and noise, particularly important for handheld power tools and medical devices. Terminal connections are reinforced to withstand vibration and repeated plugging cycles.
OEM customers can specify shaft diameter (8mm, 10mm, or 12mm), shaft length, and end configurations including flat, keyway, D-cut, knurling, or gear cutting. Gearbox attachments (planetary or spur) with reduction ratios from 3:1 to 100:1 are available for torque multiplication. For speed feedback, magnetic or optical encoders can be integrated. Custom lead wire length, connector terminations (Molex, JST, AMP, Deutsch), and EMI suppression components (capacitors, varistors) are supported for volume orders.
Each M40-70 motor undergoes 100% final inspection including no-load speed, no-load current, insulation resistance, dielectric strength, mechanical runout, and vibration testing. Production follows ISO 9001:2015 quality management processes. RoHS and REACH compliance documentation is available. Custom winding configurations and performance curves can be developed for OEM volume orders. Sample motors are available for engineering evaluation.
