Switch to turn off motor and another to turn the motor on

Question

I have a DC motor that turns a gear which then has an arm that will hit a switch which turns the motor off.

Is there a way for me to build this without using a microcontroller?

Like I start the motor with switch1 then the motor hits switch2 which then turns the motor off, so to activate it again I need to press switch1.

Answer 1

A possibly simpler method is as follows:

• Set the motor up with a wheel which engages a microswitch (or similar)

Wire the microswitch as SW1, the starting switch as SW2:

With SW2 unpressed, the motor will go until the tab engages the microswitch, breaking the normally-closed side. It stays there until you press the start switch SW2 for long enough to move the wheel off the microswitch.

I once made a doorbell like this, out of a CD-ROM motor and a music-box mechanism. It was arranged to play the whole of the Pink Panther tune. All was fine until the tab broke and it played for about an hour: everybody was hoping their patience lasted longer than the battery.

The tab was glued onto the wheel, marked 2 in Wikipedia image:

Answer 2

Yes. You can relatively easily do this: the first momentary switch turns on a relay, which is normally off, and is parallel to that switch. So, turning on the current through the relay's coil makes the relay stay on (we call that a "latch"):

^{simulate this circuit – Schematic created using CircuitLab}

To turn the motor off, you need to turn the current through the relay. Easy, use a momentary switch that's normally closed to interrupt your current:

^{simulate this circuit}