US Patent 12009149 Push-pull solenoid

A push-pull solenoid is provided with a cylindrical guide member that is fixed to a case. A circular outer peripheral surface of a plunger is in contact with a friction guide surface formed on a circular inner peripheral surface of the guide member, and slides along the friction guide surface. Frictional force due to contact with the friction guide surface is always acting on the plunger, so it is possible to suppress impact-like contact of the plunger with an object to be manipulated during suctioning, and vibration and noise caused thereby. Moreover, over-recovery and falling-out of the plunger after suction is released can also be prevented.