How it works
A pull-type solenoid operates based on the electromagnetic force. It consists of a coil of wire wrapped around a bobbin. When current passes through the copper coil, it generates a magnetic field. This field exerts a force on a ferromagnetic plunger (or armature) within the coil. In a pull-type solenoid, the magnetic field pulls the plunger into the coil, producing linear motion. When the current is turned off, a built in return spring or other mechanical mechanism pushes the plunger back to its original position, deactivating the solenoid.
The structure
Solenoid Coil: A wound component that generates the necessary magnetic field when an electric current is applied. The solenoid coil is typically made of copper wire and is wound helically around a cylinder.
Plunger: The movable part of a solenoid, typically made of a ferromagnetic material such as iron or a magnetic alloy. The plunger is designed to be pulled into the coil when the solenoid is powered on.
Return Spring: This component is used to return the plunger to its original position when the current to the coil is interrupted. The spring is usually located at one end of the plunger and is compressed when the plunger is pulled into the coil.
Frame or Housing: Provides mechanical support and protection for the coil and plunger. The frame can be open or closed, depending on the application requirements.
Application
Locking system: Pull solenoids are commonly used in electric locks. The pulling force of the solenoid can be used to unlock or lock the lock, thus achieving remote or automated access control.
Industrial Automation: They are used in various industrial automation systems to perform tasks such as moving mechanical parts, operating valves, and actuating switches. For example, in a production line, a pull solenoid can be used to move a part to a specific position.
Robotics: Pull solenoids can be used to actuate the joints or limbs of robots, providing the linear motion necessary for precise manipulation and locomotion.
Vending machines: In vending machines, pull solenoids can be used to dispense merchandise. For example, when a user purchases an item, the solenoid pulls a mechanism that releases the selected item.
Pinball Machines: They are used to pull the firing lever in pinball machines, providing the force needed to launch the ball.