- Pololu 24V 37Dx65L mm 6.3:1 Metal Gearmotor w/ 64 CPR Encoder (Helical Pinion)
- Features a robust brushed DC motor with a 6.25:1 metal gearbox
- Integrated quadrature encoder provides a resolution of 64 counts per revolution
- Comes with a 16 mm-long, 6 mm-diameter D-shaped output shaft
The Pololu 24V 37Dx65L mm 6.3:1 Metal Gearmotor w/ 64 CPR Encoder (Helical Pinion) is a robust brushed DC motor, equipped with a 6.25:1 metal gearbox and an integrated quadrature encoder. This encoder provides a resolution of 64 counts per revolution of the motor shaft, equating to 400 counts per revolution of the gearbox’s output shaft. The gearbox is primarily composed of spur gears, however, it incorporates helical gears in the first stage to minimize noise and enhance efficiency. The units come with a 16 mm-long, 6 mm-diameter D-shaped output shaft.
This gearmotor is also available without an encoder. It features a voltage no-load performance stall extrapolation of 24 V 1600 RPM, 100 mA 3.5 kg⋅cm (49 oz⋅in), 3 A. The precise gear ratio is calculated as (25x30) / (10x12) = 6.25/1.
With a diameter of 37 mm (1.46″), this gearmotor is one of the largest and most powerful available.
The gearboxes are primarily composed of spur gears, but they incorporate helical gears in the first stage to reduce noise and improve efficiency. On units with encoders, the encoder portion is safeguarded by a black plastic end cap, which can be easily removed if access to the encoder is required or to slightly reduce the overall gearmotor size.
The gearmotor employs a two-channel Hall effect encoder to sense the rotation of a magnetic disk on a rear protrusion of the motor shaft. The quadrature encoder provides a resolution of 64 counts per revolution of the motor shaft when counting both edges of both channels. To compute the counts per revolution of the gearbox output, the gear ratio is multiplied by 64.
The face plate features six evenly spaced mounting holes around the outer edge, threaded for M3 screws. These mounting holes form a regular hexagon and the centers of neighboring holes are 15.5 mm apart. The 6 mm diameter gearbox output shaft is compatible with the Pololu universal aluminum mounting hub for 6mm shafts. This can be used to mount larger Pololu wheels (80mm- and 90mm-diameter) or custom wheels and mechanisms to the gearmotor’s output shaft.
