Product Overview

The RK-520TB-17400 is a carbon brush DC motor built on the RK-520TB platform, a 33mm diameter micro motor family that has been supplied to smart sanitary ware makers across Europe, Japan and North America. Rated at 12V DC with a no-load speed of 5500RPM and roughly 260 g.cm of stall torque, it bridges the gap between a plain toy-grade micro motor and a gear motor assembly: strong enough to lift a toilet lid through a 210:1 gearbox (about 27 kgf.cm output), compact enough to sit inside a 31 x 33mm envelope.

The 9.3 +/- 0.5mm long shaft with a 2mm diameter is the standard long-shaft version, which gives the gearbox or coupling enough shaft engagement to avoid wobble after long duty cycles. Two M2.6 x 0.45 mounting holes on a 26mm diagonal pitch keep the motor fixed under torque reversal, one of the most common failure points in flip-cover mechanisms.

Key Specifications

Why This Motor Works in Smart Toilet Seats

• Carbon brush commutation gives a soft start and a clean, quiet torque ramp - important when a lid must open in about 4 seconds without a visible jerk.
• Flat speed-torque curve keeps the opening time consistent whether the lid is light or heavy.
• Low coasting inertia after power-off lets the controller park the lid precisely with a simple limit switch instead of an encoder.
• Graphite-copper brush grade keeps electrical noise low enough to run alongside a capacitive touch panel.

Platform Customization

Because every flip-cover mechanism is different, the RK-520TB platform is offered as a configurable base: voltage from 3V to 24V, no-load speed from 3000RPM to 5900RPM on the standard winding set, shaft length and shaft steps machined to drawing, PVC or silicone lead wires, JST / Molex connectors, and EMC suppression (capacitor plus ferrite) for CE-bound products. Tooling for a new shaft is typically ready in 12-15 days.

Applications

Automatic toilet seat and smart bidet flip covers, household appliances, air pumps and pressure pumps, actuator drives, small winches and other light-duty motion modules where a compact brushed DC motor with a custom shaft is required.

Quality, Packing and Delivery

• 100% run-in and speed-current test on every motor before packing.
• Brush life verified by continuous 500-hour load testing on each production batch.
• RoHS and REACH compliant materials, ISO 9001 and IATF 16949 production system, 20 years of micro motor manufacturing experience.
• Packed in anti-static bags with shockproof foam, then export cartons of 200 pieces.
• Sample lead time 7 days; production lead time 35-45 days after deposit.