Electrically heated choke having improved control

摘要

An automatic choke mechanism including an electrical heater and a circuit for energizing the heater so that the choke is opened first at a relatively rapid rate and later at a slower rate. The means for heating the choke comprises an N.T.C. device in series circuit with a P.T.C. heater and a temperature responsive shunting circuit for shunting the N.T.C.