Overrun braking system and method

An automatic flush valve system for evacuating waste, comprising:

• a motor;
• a gear train mechanically coupled to the motor;
• a switch cam mechanically coupled to the gear train;
• a rod cam mechanically coupled to the gear train;
• a valve mechanically coupled to the rod cam;
• sensing logic electrically coupled to the motor to initiate a rotation of a motor shaft;
• a mechanical switch mechanically coupled to the switch cam and electrically coupled to the motor to sustain the rotation of the motor shaft;
• and
• braking logic electrically coupled to the sensing logic and the motor, the sensing logic configured to interrupt a power connection to the motor and the braking logic configured to terminate rotation of the motor shaft by converting the mechanical energy of the motor shaft into thermal energy.

An automatic braking method for use on an automatic flushing device, comprising:

• receiving an actuation signal;
• actuating an electronic switch to initiate a rotation of a switch cam and an opening of a valve;
• actuating a mechanical switch when a cutout portion of the switch cam is in contact with a portion of the mechanical switch;
• and
• closing the valve when the portion of the mechanical switch is outside of the cutout portion.