The Basics of Solenoids and Electric Motors

By: Chad M.

Basically an electric motor is a mechanical device that switches electric energy into mechanical energy by passing an electric current through a wire loop contained within a magnetic field. A solenoid, universally used in all types of motors from power door locks to starters and is simply a round coil of wire that's been insulated and used to create a magnetic field in the atmosphere of this current.

Solenoids are a specially engineered electromagnet in which a coil of wire is wrapped around a specially shaped core made of steel or iron, it is an integral component in all sizes of motors.

Solenoids work like this: when electrical current goes through the loop of wire, a magnetic field accumulates around it. A iron or steel path for this force to flow into significantly increases the strength of the magnetic field. Because magnetic energy attempts to take a specific path, flowing from the center of a coil, out one end, down the sides and then reversing that path. If a iron or steel core, called a solenoid, is shaped to fit this path, it will then direct the flow of magnetism through it.

When a gap is left in the core design, the magnetic flux will flow around the path until it is stopped by the resulting breach. The armature of a solenoid will fill the gap; thus, when the current flows through the coil, it will attract this moveable plunger into the gap, which then completes the electrical circuit. This plunger can subsequently be attached to various mechanical parts, which, in turn, will cause them to move in a particular, defined direction. Depending on which end of the armature is connected to the solenoid, a pushing or pulling motion results. Very often, springs are used to keep the plunger position set to open.

Electromagnetic motors are based on the basic principle that all current-carrying wire within a magnetic field contains a amount of mechanical force. The larger the motor and the greater the electromagnetic field, the more power is produced. A string of solenoid switches and check valves can be used to harness this power in a specific manner, depending on the force and direction required. The muscle behind any motor is governed by various factors including the number of turns in the coil, the quantity of current flowing through it, the distance end to end of the coil and the magnetic purity of the iron or steel used in the moveable parts.

In closing, by applying the basics of electromagnetic knowledge and by modifying the parts to withstand the relevant pressure, all motors, regardless of their size operate on this same scientific standard.

Technology
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 

» More on Technology