Electric window opener

With parts available in the construction market and a 12V motor with gearing , I made ​​a window opener. I use it  also for ventilation  strips above the windows. The engine drives a piece of threaded rod that is connected to a guide rail by a nut The boundaries are determined by reed switches and a magnet.

The schema

The current flows through the contacts 14-12, through the engine, contacts 5-3 and by the transistor Q1. If the magnet  closes reed contact the Q1 will not conduct anymore and the motor stops.

When switch S1 closes the contacts of the relay K1 and the motor is turned the other direction because the  current flows through contacts  1-5 and  12-16, through transistor Q2.  The magnet will close reed contact S3 when the rail is fully extente.

. The 4 diodes  is  to protect the transistors


  • 1 x  magnet N-35 M 5 0 X 22
  • 1 x  12 V motor with gearbox
  • 1 x .RELAIS 5A 2XUM 12V
  • 4 x  1N4007 1000V 1A
  • 2 x  Transistor TIP3055 STM, TO218
  • 2 x resistors 1K

click picture to enlarge