What is a Voice Coil Motor?

Imagine a speaker in your radio or phone. Inside, there’s a part that makes sound by moving quickly. A VCM is like that part, but it’s used to move other things, not just make sound.

A VCM has two main parts:

• A coil of wire. It’s like a long, skinny rope made of metal, usually copper.
• A magnet. A special, strong magnet called a Neodymium magnet or an NdFeB magnet. We make these magnets! See our Neodymium Magnets Factory.

How Does a VCM Work?

It’s all about electricity and magnets!

1. Electricity flows through the coil.
2. This makes the coil act like a magnet too!
3. The coil magnet and the strong NdFeB magnet push and pull each other.
4. This pushing and pulling makes the coil move!
5. If you want to do electromagnetic modeling, you use a Lorentz force equation.

This is called the Lorentz force principle. It’s like magic, but it’s science!

Why are VCMs So Good?

VCMs are better than some other motors in many ways:

VCMs are like the superheroes of motors!

We are experts at making the strong NdFeB magnets that make VCMs work so well. These are Permanent Magnet solutions.

What Makes a Good VCM?

• Strong Magnets: The stronger the magnet, the stronger the VCM. We use NdFeB magnets because they are the strongest kind! You can choose a Magnet Grade like N52, which is super strong! Or N42, which is still very strong.
• Good Coil: The coil must be made of a good metal, like copper. It needs to let electricity flow easily. Coil winding materials is very important!
• Keeping it Cool: VCMs can get hot. We need to keep them cool so they keep working.
• Dynamic response time is very important to know, when sizing your motor needs.

Fact: A VCM with an N52 magnet can be 15% stronger than one with an N42 magnet! But it might also cost a little more.

Where Do We Use VCMs?

VCMs are used in lots of cool things:

• Robots: They help robots move their arms and legs.
• Space: They help move things on spaceships and satellites.
• Doctors: They help doctors use special tools during surgery.
• Cameras: VCM is commonly found in optical focusing systems.
• Hard Disk Drives: VCMs help move the parts that read and write data.
• Speakers: Yes, they’re in speakers too!
• Automotive Actuator Applications: VCMs are used in lots of places in cars.

If you need magnets for medical devices, you need special Magnet Coating to keep them safe.

VCMs vs. Other Motors!

There are other kinds of motors, like:

1. Stepper motors
2. Servo motor alternatives
3. Solenoid vs. voice coil

VCMs are usually best when you need speed and precision.

Fun Fact: In some robots, VCMs with special NdFeB magnets make the robot move 36% faster!

Buying the Right Parts

If you are building a VCM, you need to pick the right parts. Coil impedance characteristics must be considered.

Here’s a Buyer’s Guide:

For the Magnet:

• Magnet Grade: Choose N35, N38, N40, N42, N45, N48, N50, or N52. N52 is the strongest!
• Size and Shape: We can make Customized NdFeB Magnets in any size or shape you need!
• Coating: Pick a coating to protect the magnet.

For the Coil:

• Material: Copper is usually best.
• Size: The size depends on your VCM.
• Bifilar winding configurations are neat.

For the inside of the VCM:

• You may need Ferromagnetic materials.
• You should consider Magnetic circuit design.
• You may need good Magnetic shielding methods.

Important! We are NdFeB magnet experts! We can help you choose the perfect magnet for your VCM. Many of our current clients use our magnets for industrial automation uses.

Our Magnets are the Best!

• We make high-quality NdFeB magnets.
• We can make any size or shape.
• We can help you design your VCM.
• Fault-tolerant actuator design is something we value.
• Our magnets make VCMs stronger and last longer. Use of a Halbach array can make the magnetic flux density more uniform.
• We can find uses for neodymium magnets in wind turbines also!

Fact: Our N50 magnets can make a VCM 15% stronger than average!

More Cool Things About VCMs

Halbach Arrays

This is a special way to arrange magnets. It makes the magnetic field stronger on one side and weaker on the other. This can make VCMs even better!

Cooling VCMs

VCMs can get hot. To keep them cool, you can:

• Use a fan.
• Use special metal to pull heat away.
• Use water cooling!
• Use the best **Coil cooling techniques.
• Think of the heat transfer coefficient.

Using VCMs Safely

• Don’t let them get too hot.
• Use the right electricity.
• Be careful of strong magnets!
• Check for Electromagnetic interference (EMI).

VCMs in the Future

VCMs will be used in even more cool things:

• Tiny robots for medicine.
• Self-driving cars.
• New kinds of spaceships.
• MEMS-based voice coils.

We are ready for the future! We are always making better NdFeB magnets for the VCMs of tomorrow.

Questions You Might Have: