We were asked to provide a solution for driving a robotized gearbox (clutch motor, speed selector motor, quick coupling motor) that would meet the following needs:

• maximum containment of external dimensions
• high performance
• strong impact resistance
• high resistance to stress from accelerations up to 100 g
• operation in the temperature range from – 40°C to + 140°C
• maximum speed of implementation
• IP protection: IP 69

 
The solution and its advantages

We have designed a small motor (l=90mm and Ø=50mm) with four poles with a starting torque of 2Nm, sealed with silicone seals that guarantee tightness and resistance up to 245°C.

The plastic material used for the brush holder was chosen to withstand high temperatures, characterised by a melting point of 300°C.

The wire harnesses are co-moulded together with the brush holder and are derived from the technology used in Formula 1, where the insulating material must withstand temperatures comparable to those mentioned.

Much attention has been paid to optimising the layout of the brush holder, given the presence of the numerous components and the four 90° magnets of the motor.

Finally, two covers positioned above and below the brush holder ensured adequate protection against carbon dust produced by brush wear.