Ring magnet sliding on iron core solenoid actuator

In summary, a ring magnet sliding on an iron core solenoid actuator is an electromechanical device that uses a solenoid and a ring magnet to create linear motion. When an electric current is passed through the solenoid, it creates a magnetic field that interacts with the ring magnet, causing it to slide along the iron core. This type of actuator has various applications in industries such as manufacturing, robotics, and consumer electronics, and offers advantages such as a high force-to-size ratio and precise motion. However, it also has limitations, including the need for a continuous power supply and potential wear on components.
  • #1
xrcv
1
0
Hi everyone, I have lots of (potentially dumb) questions about this "project" I'm working on. It's a voice coil actuator, but with things a bit reversed. Here's how a regular voice-coil actuator is constructed:

lvcm-044-051-01p1.jpg

The rod that is inside the coil is a magnet and the outer cylinder continues the magnetic path, sort of like an axial horse-shoe magnet. The coil and magnet push or pull each other, based on polarity..

I already ordered a magnet, but in the meantime I found some cheap ring-magnets, still axially polarized, and I'm wondering how well this would work:
ringmagnet.jpg


I actually already did this experiment with two coils - one loose to slide and one fixed and they did repel or attract each other nicely along the iron bar. With the ring magnet, I suppose the ring and the iron rod inside the ring magnetic fields will move in opposite directions, i.e the iron bar will be "closing" the magnetic field of the ring magnet.

So, then the coil produces a magnetic field and it's either in the same, or in the opposing direction of the field in the rod inside the magnet, moving it left or right..

What I was first wondering is about saturation...If the magnetic field of the magnet saturates the iron rod in it, the magnetic field created by the coil won't be able to "pass" through that point. Is that correct? Or am I wrong?

Can one of the magnetic fields "overpower" the other, so that no linear motion will be efficiently produced? Also, what if I close the magnetic path of the iron rod, would this require less power to produce the same force?

Also I found a thread here:https://www.physicsforums.com/threa...ally-magnetized-permanent-ring-magnet.867355/

that said if the ring magnet is long, the magnetic field near the center will be almost zero. I suppose with an iron rod inside, this is not the case?

Will the force of the movement be linearly proportional to the length of the magnet?

Guess I should just test it, but thought I'd ask before ordering the magnets.
 
Physics news on Phys.org
  • #2


Hi there,

Thank you for sharing your project with us. It sounds like you have some interesting ideas and questions about using a ring magnet in a voice coil actuator. I'll do my best to address your questions and provide some guidance.

Firstly, using a ring magnet instead of a cylindrical magnet in a voice coil actuator is definitely possible. However, there are some factors to consider that may affect the performance of the actuator.

Regarding saturation, you are correct that if the magnetic field of the ring magnet saturates the iron rod inside, it may limit the effectiveness of the actuator. However, this will depend on the strength of the magnet and the size of the iron rod. It's possible that the iron rod may not saturate at all, or only slightly, which would allow the magnetic field of the coil to pass through and produce movement.

In terms of one magnetic field overpowering the other, it is possible for the magnetic fields to cancel each other out if they are in opposite directions. This could potentially limit the effectiveness of the actuator. It's important to carefully consider the strength and orientation of both the ring magnet and the coil to ensure they work together effectively.

Closing the magnetic path of the iron rod may indeed require less power to produce the same force. This is because the closed path allows for a more efficient transfer of energy between the magnet and the coil.

Regarding the thread you found about the magnetic field inside a long ring magnet, this is correct. The magnetic field near the center of a long ring magnet will be close to zero. However, with an iron rod inside, the magnetic field will be affected and may not be zero. It's difficult to say exactly what the field strength will be without knowing the specifics of your setup.

As for the force of the movement being proportional to the length of the magnet, this will also depend on the strength of the magnet and the size of the iron rod. In general, a longer magnet may provide a stronger magnetic field, but it's important to consider all the other factors as well.

In summary, using a ring magnet in a voice coil actuator is possible, but it's important to carefully consider all the factors that may affect its performance. I would recommend testing different configurations and measuring the force produced to determine the most effective setup for your project. I hope this helps and good luck with your experiment!
 

Related to Ring magnet sliding on iron core solenoid actuator

1. What is a ring magnet sliding on an iron core solenoid actuator?

A ring magnet sliding on an iron core solenoid actuator is a type of electromechanical device used for linear motion. It consists of a solenoid, which is a coil of wire, and an iron core that is surrounded by a ring magnet. When an electric current is passed through the solenoid, it creates a magnetic field that attracts or repels the ring magnet, causing it to slide along the iron core.

2. How does a ring magnet sliding on an iron core solenoid actuator work?

The solenoid in the actuator is connected to a power source, such as a battery. When the power is turned on, an electric current flows through the coil, creating a magnetic field. This magnetic field interacts with the magnetic field of the ring magnet, causing it to move along the iron core. The direction of the current determines the direction of motion of the ring magnet.

3. What are the applications of a ring magnet sliding on an iron core solenoid actuator?

This type of actuator is commonly used in various industrial and commercial applications, such as in automated manufacturing processes, robotic systems, and medical devices. It can also be found in consumer electronics, such as speakers and door locks.

4. What are the advantages of using a ring magnet sliding on an iron core solenoid actuator?

One of the main advantages of this type of actuator is its high force-to-size ratio. It can produce a significant amount of force in a compact size, making it suitable for applications with limited space. It also offers precise and repeatable linear motion, making it ideal for applications that require accurate positioning.

5. Are there any limitations to using a ring magnet sliding on an iron core solenoid actuator?

One limitation of this type of actuator is that it requires a continuous supply of electricity to maintain its position. This means that if the power is cut off, the actuator will lose its holding force and the ring magnet will slide back to its original position. Additionally, the sliding motion can create friction and wear on the components, so regular maintenance may be required to ensure optimal performance.

Similar threads

Replies
21
Views
2K
  • Electromagnetism
2
Replies
43
Views
1K
Replies
6
Views
2K
Replies
8
Views
1K
Replies
4
Views
422
Replies
7
Views
4K
Replies
3
Views
5K
  • Electromagnetism
Replies
7
Views
1K
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
5
Views
290
Back
Top